diff --git a/Content.Client/Arcade/BlockGameMenu.cs b/Content.Client/Arcade/BlockGameMenu.cs
index d2ae617356..c55d27e0cb 100644
--- a/Content.Client/Arcade/BlockGameMenu.cs
+++ b/Content.Client/Arcade/BlockGameMenu.cs
@@ -90,8 +90,8 @@ namespace Content.Client.Arcade
             _highscoresRootContainer = new PanelContainer
             {
                 PanelOverride = rootBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             var c = new Color(OverlayBackgroundColor.R,OverlayBackgroundColor.G,OverlayBackgroundColor.B,220);
@@ -104,20 +104,20 @@ namespace Content.Client.Arcade
             var menuInnerPanel = new PanelContainer
             {
                 PanelOverride = innerBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             _highscoresRootContainer.AddChild(menuInnerPanel);
 
             var menuContainer = new VBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center
             };
 
             menuContainer.AddChild(new Label{Text = Loc.GetString("Highscores")});
-            menuContainer.AddChild(new Control{CustomMinimumSize = new Vector2(1,10)});
+            menuContainer.AddChild(new Control{MinSize = new Vector2(1,10)});
 
             var highScoreBox = new HBoxContainer();
 
@@ -126,14 +126,14 @@ namespace Content.Client.Arcade
                 Align = Label.AlignMode.Center
             };
             highScoreBox.AddChild(_localHighscoresLabel);
-            highScoreBox.AddChild(new Control{CustomMinimumSize = new Vector2(40,1)});
+            highScoreBox.AddChild(new Control{MinSize = new Vector2(40,1)});
             _globalHighscoresLabel = new Label
             {
                 Align = Label.AlignMode.Center
             };
             highScoreBox.AddChild(_globalHighscoresLabel);
             menuContainer.AddChild(highScoreBox);
-            menuContainer.AddChild(new Control{CustomMinimumSize = new Vector2(1,10)});
+            menuContainer.AddChild(new Control{MinSize = new Vector2(1,10)});
             _highscoreBackButton = new Button
             {
                 Text = Loc.GetString("Back"),
@@ -156,8 +156,8 @@ namespace Content.Client.Arcade
             _gameOverRootContainer = new PanelContainer
             {
                 PanelOverride = rootBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             var innerBack = new StyleBoxTexture
@@ -169,25 +169,25 @@ namespace Content.Client.Arcade
             var menuInnerPanel = new PanelContainer
             {
                 PanelOverride = innerBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             _gameOverRootContainer.AddChild(menuInnerPanel);
 
             var menuContainer = new VBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center
             };
 
             menuContainer.AddChild(new Label{Text = Loc.GetString("Gameover!"),Align = Label.AlignMode.Center});
-            menuContainer.AddChild(new Control{CustomMinimumSize = new Vector2(1,10)});
+            menuContainer.AddChild(new Control{MinSize = new Vector2(1,10)});
 
 
             _finalScoreLabel = new Label{Align = Label.AlignMode.Center};
             menuContainer.AddChild(_finalScoreLabel);
-            menuContainer.AddChild(new Control{CustomMinimumSize = new Vector2(1,10)});
+            menuContainer.AddChild(new Control{MinSize = new Vector2(1,10)});
 
             _finalNewGameButton = new Button
             {
@@ -214,8 +214,8 @@ namespace Content.Client.Arcade
             _menuRootContainer = new PanelContainer
             {
                 PanelOverride = rootBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             var innerBack = new StyleBoxTexture
@@ -227,8 +227,8 @@ namespace Content.Client.Arcade
             var menuInnerPanel = new PanelContainer
             {
                 PanelOverride = innerBack,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center,
+                HorizontalAlignment = HAlignment.Center
             };
 
             _menuRootContainer.AddChild(menuInnerPanel);
@@ -236,8 +236,8 @@ namespace Content.Client.Arcade
 
             var menuContainer = new VBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center
             };
 
             _newGameButton = new Button
@@ -250,7 +250,7 @@ namespace Content.Client.Arcade
                 _owner.SendAction(BlockGamePlayerAction.NewGame);
             };
             menuContainer.AddChild(_newGameButton);
-            menuContainer.AddChild(new Control{CustomMinimumSize = new Vector2(1,10)});
+            menuContainer.AddChild(new Control{MinSize = new Vector2(1,10)});
 
             _scoreBoardButton = new Button
             {
@@ -259,7 +259,7 @@ namespace Content.Client.Arcade
             };
             _scoreBoardButton.OnPressed += (e) => _owner.SendAction(BlockGamePlayerAction.ShowHighscores);
             menuContainer.AddChild(_scoreBoardButton);
-            _unpauseButtonMargin = new Control {CustomMinimumSize = new Vector2(1, 10), Visible = false};
+            _unpauseButtonMargin = new Control {MinSize = new Vector2(1, 10), Visible = false};
             menuContainer.AddChild(_unpauseButtonMargin);
 
             _unpauseButton = new Button
@@ -301,35 +301,35 @@ namespace Content.Client.Arcade
             _levelLabel = new Label
             {
                 Align = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
             _gameRootContainer.AddChild(_levelLabel);
             _gameRootContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(1,5)
+                MinSize = new Vector2(1,5)
             });
 
             _pointsLabel = new Label
             {
                 Align = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
             _gameRootContainer.AddChild(_pointsLabel);
             _gameRootContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(1,10)
+                MinSize = new Vector2(1,10)
             });
 
             var gameBox = new HBoxContainer();
             gameBox.AddChild(SetupHoldBox(backgroundTexture));
             gameBox.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(10,1)
+                MinSize = new Vector2(10,1)
             });
             gameBox.AddChild(SetupGameGrid(backgroundTexture));
             gameBox.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(10,1)
+                MinSize = new Vector2(10,1)
             });
             gameBox.AddChild(SetupNextBox(backgroundTexture));
 
@@ -337,7 +337,7 @@ namespace Content.Client.Arcade
 
             _gameRootContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(1,10)
+                MinSize = new Vector2(1,10)
             });
 
             _pauseButton = new Button
@@ -369,7 +369,7 @@ namespace Content.Client.Arcade
             var gamePanel = new PanelContainer
             {
                 PanelOverride = back,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 60
             };
             var backgroundPanel = new PanelContainer
@@ -393,16 +393,16 @@ namespace Content.Client.Arcade
             var grid = new GridContainer
             {
                 Columns = 1,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 20
             };
 
             var nextBlockPanel = new PanelContainer
             {
                 PanelOverride = previewBack,
-                CustomMinimumSize = BlockSize * 6.5f,
-                SizeFlagsHorizontal = SizeFlags.None,
-                SizeFlagsVertical = SizeFlags.None
+                MinSize = BlockSize * 6.5f,
+                HorizontalAlignment = HAlignment.Left,
+                VerticalAlignment = VAlignment.Top
             };
             var nextCenterContainer = new CenterContainer();
             _nextBlockGrid = new GridContainer
@@ -431,16 +431,16 @@ namespace Content.Client.Arcade
             var grid = new GridContainer
             {
                 Columns = 1,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 20
             };
 
             var holdBlockPanel = new PanelContainer
             {
                 PanelOverride = previewBack,
-                CustomMinimumSize = BlockSize * 6.5f,
-                SizeFlagsHorizontal = SizeFlags.None,
-                SizeFlagsVertical = SizeFlags.None
+                MinSize = BlockSize * 6.5f,
+                HorizontalAlignment = HAlignment.Left,
+                VerticalAlignment = VAlignment.Top
             };
             var holdCenterContainer = new CenterContainer();
             _holdBlockGrid = new GridContainer
@@ -625,7 +625,7 @@ namespace Content.Client.Arcade
                     _nextBlockGrid.AddChild(new PanelContainer
                     {
                         PanelOverride = new StyleBoxFlat {BackgroundColor = c},
-                        CustomMinimumSize = BlockSize,
+                        MinSize = BlockSize,
                         RectDrawClipMargin = 0
                     });
                 }
@@ -647,7 +647,7 @@ namespace Content.Client.Arcade
                     _holdBlockGrid.AddChild(new PanelContainer
                     {
                         PanelOverride = new StyleBoxFlat {BackgroundColor = c},
-                        CustomMinimumSize = BlockSize,
+                        MinSize = BlockSize,
                         RectDrawClipMargin = 0
                     });
                 }
@@ -665,7 +665,7 @@ namespace Content.Client.Arcade
                     _gameGrid.AddChild(new PanelContainer
                     {
                         PanelOverride = new StyleBoxFlat {BackgroundColor = c},
-                        CustomMinimumSize = BlockSize,
+                        MinSize = BlockSize,
                         RectDrawClipMargin = 0
                     });
                 }
diff --git a/Content.Client/Arcade/SpaceVillainArcadeMenu.cs b/Content.Client/Arcade/SpaceVillainArcadeMenu.cs
index e8897e7ebd..588b8f4f8c 100644
--- a/Content.Client/Arcade/SpaceVillainArcadeMenu.cs
+++ b/Content.Client/Arcade/SpaceVillainArcadeMenu.cs
@@ -9,7 +9,6 @@ namespace Content.Client.Arcade
 {
     public class SpaceVillainArcadeMenu : SS14Window
     {
-        protected override Vector2? CustomSize => (400, 200);
         public SpaceVillainArcadeBoundUserInterface Owner { get; set; }
 
         private readonly Label _enemyNameLabel;
@@ -21,6 +20,7 @@ namespace Content.Client.Arcade
         private readonly Button[] _gameButtons = new Button[3]; //used to disable/enable all game buttons
         public SpaceVillainArcadeMenu(SpaceVillainArcadeBoundUserInterface owner)
         {
+            MinSize = SetSize = (400, 200);
             Title = Loc.GetString("Space Villain");
             Owner = owner;
 
diff --git a/Content.Client/Chat/ChatBox.cs b/Content.Client/Chat/ChatBox.cs
index 0269076663..7c4c650752 100644
--- a/Content.Client/Chat/ChatBox.cs
+++ b/Content.Client/Chat/ChatBox.cs
@@ -9,7 +9,7 @@ using Robust.Shared.Utility;
 
 namespace Content.Client.Chat
 {
-    public class ChatBox : MarginContainer
+    public class ChatBox : Control
     {
         public delegate void TextSubmitHandler(ChatBox chatBox, string text);
 
@@ -23,7 +23,7 @@ namespace Content.Client.Chat
         public Button LocalButton { get; }
         public Button OOCButton { get; }
         public Button AdminButton { get; }
-        public Button DeadButton { get;  }
+        public Button DeadButton { get; }
 
         /// <summary>
         ///     Default formatting string for the ClientChatConsole.
@@ -36,13 +36,6 @@ namespace Content.Client.Chat
 
         public ChatBox()
         {
-            /*MarginLeft = -475.0f;
-            MarginTop = 10.0f;
-            MarginRight = -10.0f;
-            MarginBottom = 235.0f;
-
-            AnchorLeft = 1.0f;
-            AnchorRight = 1.0f;*/
             MouseFilter = MouseFilterMode.Stop;
 
             var outerVBox = new VBoxContainer();
@@ -50,7 +43,7 @@ namespace Content.Client.Chat
             var panelContainer = new PanelContainer
             {
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#25252aaa")},
-                SizeFlagsVertical = SizeFlags.FillExpand
+                VerticalExpand = true
             };
             var vBox = new VBoxContainer();
             panelContainer.AddChild(vBox);
@@ -59,15 +52,8 @@ namespace Content.Client.Chat
             outerVBox.AddChild(panelContainer);
             outerVBox.AddChild(hBox);
 
-
-            var contentMargin = new MarginContainer
-            {
-                MarginLeftOverride = 4, MarginRightOverride = 4,
-                SizeFlagsVertical = SizeFlags.FillExpand
-            };
-            Contents = new OutputPanel();
-            contentMargin.AddChild(Contents);
-            vBox.AddChild(contentMargin);
+            Contents = new OutputPanel {Margin = new Thickness(4, 0), VerticalExpand = true};
+            vBox.AddChild(Contents);
 
             Input = new HistoryLineEdit();
             Input.OnKeyBindDown += InputKeyBindDown;
@@ -78,7 +64,8 @@ namespace Content.Client.Chat
             {
                 Text = Loc.GetString("All"),
                 Name = "ALL",
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Expand,
+                HorizontalExpand = true,
+                HorizontalAlignment = HAlignment.Right,
                 ToggleMode = true,
             };
 
diff --git a/Content.Client/Chat/SpeechBubble.cs b/Content.Client/Chat/SpeechBubble.cs
index 581010b8d2..b2639281d5 100644
--- a/Content.Client/Chat/SpeechBubble.cs
+++ b/Content.Client/Chat/SpeechBubble.cs
@@ -74,17 +74,13 @@ namespace Content.Client.Chat
 
             ForceRunStyleUpdate();
 
-            ContentHeight = bubble.CombinedMinimumSize.Y;
+            bubble.Measure(Vector2.Infinity);
+            ContentHeight = bubble.DesiredSize.Y;
             _verticalOffsetAchieved = -ContentHeight;
         }
 
         protected abstract Control BuildBubble(string text);
 
-        protected override Vector2 CalculateMinimumSize()
-        {
-            return (base.CalculateMinimumSize().X, 0);
-        }
-
         protected override void FrameUpdate(FrameEventArgs args)
         {
             base.FrameUpdate(args);
@@ -122,7 +118,7 @@ namespace Content.Client.Chat
             LayoutContainer.SetPosition(this, screenPos);
 
             var height = MathHelper.Clamp(lowerCenter.Y - screenPos.Y, 0, ContentHeight);
-            LayoutContainer.SetSize(this, (Size.X, height));
+            SetHeight = height;
         }
 
         private void Die()
diff --git a/Content.Client/ClientNotifyManager.cs b/Content.Client/ClientNotifyManager.cs
index 6a647a82f8..d9c32ab9fa 100644
--- a/Content.Client/ClientNotifyManager.cs
+++ b/Content.Client/ClientNotifyManager.cs
@@ -102,7 +102,8 @@ namespace Content.Client
             };
 
             _userInterfaceManager.PopupRoot.AddChild(label);
-            var minimumSize = label.CombinedMinimumSize;
+            label.Measure(Vector2.Infinity);
+            var minimumSize = label.DesiredSize;
 
             label.InitialPos = (coordinates.Position / _userInterfaceManager.UIScale) - minimumSize / 2;
             LayoutContainer.SetPosition(label, label.InitialPos);
@@ -149,7 +150,7 @@ namespace Content.Client
 
                 var position = Entity == null
                     ? InitialPos
-                    : (_eyeManager.CoordinatesToScreen(Entity.Transform.Coordinates).Position / UIScale) - CombinedMinimumSize / 2;
+                    : (_eyeManager.CoordinatesToScreen(Entity.Transform.Coordinates).Position / UIScale) - DesiredSize / 2;
 
                 LayoutContainer.SetPosition(this, position - (0, 20 * (TimeLeft * TimeLeft + TimeLeft)));
 
diff --git a/Content.Client/Command/CommunicationsConsoleMenu.cs b/Content.Client/Command/CommunicationsConsoleMenu.cs
index 565f3ca670..8bfbea72a0 100644
--- a/Content.Client/Command/CommunicationsConsoleMenu.cs
+++ b/Content.Client/Command/CommunicationsConsoleMenu.cs
@@ -12,8 +12,6 @@ namespace Content.Client.Command
 {
     public class CommunicationsConsoleMenu : SS14Window
     {
-        protected override Vector2? CustomSize => new Vector2(600, 400);
-
         private CommunicationsConsoleBoundUserInterface Owner { get; set; }
         private readonly CancellationTokenSource _timerCancelTokenSource = new();
         public readonly Button EmergencyShuttleButton;
@@ -21,25 +19,26 @@ namespace Content.Client.Command
 
         public CommunicationsConsoleMenu(CommunicationsConsoleBoundUserInterface owner)
         {
+            SetSize = MinSize = (600, 400);
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("Communications Console");
             Owner = owner;
 
-            _countdownLabel = new RichTextLabel(){CustomMinimumSize = new Vector2(0, 200)};
+            _countdownLabel = new RichTextLabel(){MinSize = new Vector2(0, 200)};
             EmergencyShuttleButton = new Button();
             EmergencyShuttleButton.OnPressed += (_) => Owner.EmergencyShuttleButtonPressed();
             EmergencyShuttleButton.Disabled = !owner.CanCall;
 
-            var vbox = new VBoxContainer() {SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsVertical = SizeFlags.FillExpand};
+            var vbox = new VBoxContainer() {HorizontalExpand = true, VerticalExpand = true};
 
             vbox.AddChild(_countdownLabel);
             vbox.AddChild(EmergencyShuttleButton);
 
-            var hbox = new HBoxContainer() {SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsVertical = SizeFlags.FillExpand};
-            hbox.AddChild(new Control(){CustomMinimumSize = new Vector2(100,0), SizeFlagsHorizontal = SizeFlags.FillExpand});
+            var hbox = new HBoxContainer() {HorizontalExpand = true, VerticalExpand = true};
+            hbox.AddChild(new Control(){MinSize = new Vector2(100,0), HorizontalExpand = true});
             hbox.AddChild(vbox);
-            hbox.AddChild(new Control(){CustomMinimumSize = new Vector2(100,0), SizeFlagsHorizontal = SizeFlags.FillExpand});
+            hbox.AddChild(new Control(){MinSize = new Vector2(100,0), HorizontalExpand = true});
 
             Contents.AddChild(hbox);
 
diff --git a/Content.Client/Construction/ConstructionMenu.xaml b/Content.Client/Construction/ConstructionMenu.xaml
index 0794b6beb2..e4794cd1b3 100644
--- a/Content.Client/Construction/ConstructionMenu.xaml
+++ b/Content.Client/Construction/ConstructionMenu.xaml
@@ -1,27 +1,27 @@
 <SS14Window xmlns="https://spacestation14.io">
-    <HBoxContainer SizeFlagsHorizontal="FillExpand">
-        <VBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.45">
-            <HBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.1">
-                <LineEdit Name="SearchBar" PlaceHolder="Search" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.6"/>
-                <OptionButton Name="Category" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.4"/>
+    <HBoxContainer HorizontalExpand="True">
+        <VBoxContainer HorizontalExpand="True" SizeFlagsStretchRatio="0.45">
+            <HBoxContainer HorizontalExpand="True" VerticalExpand="True" SizeFlagsStretchRatio="0.1">
+                <LineEdit Name="SearchBar" PlaceHolder="Search" HorizontalExpand="True" SizeFlagsStretchRatio="0.6"/>
+                <OptionButton Name="Category" HorizontalExpand="True" SizeFlagsStretchRatio="0.4"/>
             </HBoxContainer>
-            <ItemList Name="RecipesList" SelectMode="Single" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.9"/>
+            <ItemList Name="RecipesList" SelectMode="Single" VerticalExpand="True" SizeFlagsStretchRatio="0.9"/>
         </VBoxContainer>
-        <Control SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.05"/>
-        <VBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.45">
-            <HBoxContainer Align="Center" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.25">
-                <TextureRect Name="TargetTexture" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.15" Stretch="KeepCentered"/>
-                <VBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.85">
-                    <RichTextLabel Name="TargetName" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.1"/>
-                    <RichTextLabel Name="TargetDesc" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.9"/>
+        <Control HorizontalExpand="True" SizeFlagsStretchRatio="0.05"/>
+        <VBoxContainer HorizontalExpand="True" SizeFlagsStretchRatio="0.45">
+            <HBoxContainer Align="Center" VerticalExpand="True" SizeFlagsStretchRatio="0.25">
+                <TextureRect Name="TargetTexture" HorizontalExpand="True" SizeFlagsStretchRatio="0.15" Stretch="KeepCentered"/>
+                <VBoxContainer HorizontalExpand="True" SizeFlagsStretchRatio="0.85">
+                    <RichTextLabel Name="TargetName" VerticalExpand="True" SizeFlagsStretchRatio="0.1"/>
+                    <RichTextLabel Name="TargetDesc" VerticalExpand="True" SizeFlagsStretchRatio="0.9"/>
                 </VBoxContainer>
             </HBoxContainer>
-            <ItemList Name="StepList" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.1"/>
-            <VBoxContainer SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.1">
-                <Button Name="BuildButton" Disabled="True" ToggleMode="True" SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.5"/>
-                <HBoxContainer SizeFlagsVertical="FillExpand" SizeFlagsStretchRatio="0.5">
-                    <Button Name="EraseButton" ToggleMode="True" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.7"/>
-                    <Button Name="ClearButton" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.3"/>
+            <ItemList Name="StepList" VerticalExpand="True" SizeFlagsStretchRatio="0.1"/>
+            <VBoxContainer VerticalExpand="True" SizeFlagsStretchRatio="0.1">
+                <Button Name="BuildButton" Disabled="True" ToggleMode="True" VerticalExpand="True" SizeFlagsStretchRatio="0.5"/>
+                <HBoxContainer VerticalExpand="True" SizeFlagsStretchRatio="0.5">
+                    <Button Name="EraseButton" ToggleMode="True" HorizontalExpand="True" SizeFlagsStretchRatio="0.7"/>
+                    <Button Name="ClearButton" HorizontalExpand="True" SizeFlagsStretchRatio="0.3"/>
                 </HBoxContainer>
             </VBoxContainer>
         </VBoxContainer>
diff --git a/Content.Client/Construction/ConstructionMenu.xaml.cs b/Content.Client/Construction/ConstructionMenu.xaml.cs
index f5831b0fce..70428b8fdb 100644
--- a/Content.Client/Construction/ConstructionMenu.xaml.cs
+++ b/Content.Client/Construction/ConstructionMenu.xaml.cs
@@ -6,7 +6,6 @@ using Robust.Client.UserInterface.CustomControls;
 using Robust.Client.UserInterface.XAML;
 using Robust.Shared.IoC;
 using Robust.Shared.Localization;
-using Robust.Shared.Maths;
 
 #nullable enable
 
@@ -57,8 +56,6 @@ namespace Content.Client.Construction
     [GenerateTypedNameReferences]
     public partial class ConstructionMenu : SS14Window, IConstructionMenuView
     {
-        protected override Vector2? CustomSize => (720, 320);
-
         public bool BuildButtonPressed
         {
             get => BuildButton.Pressed;
@@ -82,11 +79,13 @@ namespace Content.Client.Construction
 
         public ConstructionMenu()
         {
+            SetSize = MinSize = (720, 320);
+
             IoCManager.InjectDependencies(this);
             RobustXamlLoader.Load(this);
 
             Title = Loc.GetString("Construction");
-            
+
             BuildButton.Text = Loc.GetString("Place construction ghost");
             RecipesList.OnItemSelected += obj => RecipeSelected?.Invoke(this, obj.ItemList[obj.ItemIndex]);
             RecipesList.OnItemDeselected += _ => RecipeSelected?.Invoke(this, null);
diff --git a/Content.Client/GameObjects/Components/Access/IdCardConsoleWindow.cs b/Content.Client/GameObjects/Components/Access/IdCardConsoleWindow.cs
index c4e8e0370f..3df9f54340 100644
--- a/Content.Client/GameObjects/Components/Access/IdCardConsoleWindow.cs
+++ b/Content.Client/GameObjects/Components/Access/IdCardConsoleWindow.cs
@@ -34,10 +34,9 @@ namespace Content.Client.GameObjects.Components.Access
         private string _lastFullName;
         private string _lastJobTitle;
 
-        protected override Vector2? CustomSize => (650, 270);
-
         public IdCardConsoleWindow(IdCardConsoleBoundUserInterface owner, IPrototypeManager prototypeManager)
         {
+            MinSize = SetSize = (650, 270);
             _owner = owner;
             var vBox = new VBoxContainer();
 
@@ -60,7 +59,7 @@ namespace Content.Client.GameObjects.Components.Access
             _targetIdButton.OnPressed += _ => _owner.ButtonPressed(UiButton.TargetId);
 
             // Separator
-            vBox.AddChild(new Control {CustomMinimumSize = (0, 8)});
+            vBox.AddChild(new Control {MinSize = (0, 8)});
 
             // Name and job title line edits.
             vBox.AddChild(new GridContainer
@@ -76,7 +75,7 @@ namespace Content.Client.GameObjects.Components.Access
                     }),
                     (_fullNameLineEdit = new LineEdit
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        HorizontalExpand = true,
                     }),
                     (_fullNameSaveButton = new Button
                     {
@@ -91,7 +90,7 @@ namespace Content.Client.GameObjects.Components.Access
                     }),
                     (_jobTitleLineEdit = new LineEdit
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     }),
                     (_jobTitleSaveButton = new Button
                     {
@@ -116,13 +115,13 @@ namespace Content.Client.GameObjects.Components.Access
             _jobTitleSaveButton.OnPressed += _ => SubmitData();
 
             // Separator
-            vBox.AddChild(new Control {CustomMinimumSize = (0, 8)});
+            vBox.AddChild(new Control {MinSize = (0, 8)});
 
             {
                 var grid = new GridContainer
                 {
                     Columns = 5,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center
                 };
                 vBox.AddChild(grid);
 
diff --git a/Content.Client/GameObjects/Components/Actor/CharacterInfoComponent.cs b/Content.Client/GameObjects/Components/Actor/CharacterInfoComponent.cs
index b0cc06b9aa..dc0a4c4cb6 100644
--- a/Content.Client/GameObjects/Components/Actor/CharacterInfoComponent.cs
+++ b/Content.Client/GameObjects/Components/Actor/CharacterInfoComponent.cs
@@ -76,13 +76,13 @@ namespace Content.Client.GameObjects.Components.Actor
                         (SpriteView = new SpriteView { Scale = (2, 2)}),
                         new VBoxContainer
                         {
-                            SizeFlagsVertical = SizeFlags.None,
+                            VerticalAlignment = VAlignment.Top,
                             Children =
                             {
                                 (NameLabel = new Label()),
                                 (SubText = new Label
                                 {
-                                    SizeFlagsVertical = SizeFlags.None,
+                                    VerticalAlignment = VAlignment.Top,
                                     StyleClasses = {StyleNano.StyleClassLabelSubText},
 
                                 })
@@ -99,7 +99,7 @@ namespace Content.Client.GameObjects.Components.Actor
                 AddChild(new Label
                 {
                     Text = Loc.GetString("Objectives"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center
                 });
                 ObjectivesContainer = new VBoxContainer();
                 AddChild(ObjectivesContainer);
@@ -135,11 +135,11 @@ namespace Content.Client.GameObjects.Components.Actor
                         {
                             Texture = objectiveCondition.SpriteSpecifier.Frame0(),
                             Progress = objectiveCondition.Progress,
-                            SizeFlagsVertical = SizeFlags.ShrinkCenter
+                            VerticalAlignment = VAlignment.Center
                         });
                         hbox.AddChild(new Control
                         {
-                            CustomMinimumSize = (10,0)
+                            MinSize = (10,0)
                         });
                         hbox.AddChild(new VBoxContainer
                             {
diff --git a/Content.Client/GameObjects/Components/Atmos/GasAnalyzerMenu.cs b/Content.Client/GameObjects/Components/Atmos/GasAnalyzerMenu.cs
index 5afb77f1c7..89e7767e2e 100644
--- a/Content.Client/GameObjects/Components/Atmos/GasAnalyzerMenu.cs
+++ b/Content.Client/GameObjects/Components/Atmos/GasAnalyzerMenu.cs
@@ -29,7 +29,7 @@ namespace Content.Client.GameObjects.Components.Atmos
             var resourceCache = IoCManager.Resolve<IResourceCache>();
 
             Owner = owner;
-            var rootContainer = new LayoutContainer { Name = "WireRoot" };
+            var rootContainer = new LayoutContainer {Name = "WireRoot"};
             AddChild(rootContainer);
 
             MouseFilter = MouseFilterMode.Stop;
@@ -66,7 +66,7 @@ namespace Content.Client.GameObjects.Components.Atmos
                 Children =
                 {
                     (_topContainer = new VBoxContainer()),
-                    new Control {CustomMinimumSize = (0, 110)}
+                    new Control {MinSize = (0, 110)}
                 }
             };
 
@@ -78,42 +78,33 @@ namespace Content.Client.GameObjects.Components.Atmos
             var fontSmall = resourceCache.GetFont("/Fonts/Boxfont-round/Boxfont Round.ttf", 10);
 
             Button refreshButton;
-            var topRow = new MarginContainer
+            var topRow = new HBoxContainer
             {
-                MarginLeftOverride = 4,
-                MarginTopOverride = 2,
-                MarginRightOverride = 12,
-                MarginBottomOverride = 2,
+                Margin = new Thickness(4, 4, 12, 2),
                 Children =
                 {
-                    new HBoxContainer
+                    (_nameLabel = new Label
                     {
-                        Children =
-                        {
-                            (_nameLabel = new Label
-                            {
-                                Text = Loc.GetString("Gas Analyzer"),
-                                FontOverride = font,
-                                FontColorOverride = StyleNano.NanoGold,
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            }),
-                            new Control
-                            {
-                                CustomMinimumSize = (20, 0),
-                                SizeFlagsHorizontal = SizeFlags.Expand
-                            },
-                            (refreshButton = new Button {Text = "Refresh"}), //TODO: refresh icon?
-                            new Control
-                            {
-                                CustomMinimumSize = (2, 0),
-                            },
-                            (CloseButton = new TextureButton
-                            {
-                                StyleClasses = {SS14Window.StyleClassWindowCloseButton},
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            })
-                        }
-                    }
+                        Text = Loc.GetString("Gas Analyzer"),
+                        FontOverride = font,
+                        FontColorOverride = StyleNano.NanoGold,
+                        VerticalAlignment = VAlignment.Center
+                    }),
+                    new Control
+                    {
+                        MinSize = (20, 0),
+                        HorizontalExpand = true,
+                    },
+                    (refreshButton = new Button {Text = "Refresh"}), //TODO: refresh icon?
+                    new Control
+                    {
+                        MinSize = (2, 0),
+                    },
+                    (CloseButton = new TextureButton
+                    {
+                        StyleClasses = {SS14Window.StyleClassWindowCloseButton},
+                        VerticalAlignment = VAlignment.Center
+                    })
                 }
             };
 
@@ -124,37 +115,30 @@ namespace Content.Client.GameObjects.Components.Atmos
 
             var middle = new PanelContainer
             {
-                PanelOverride = new StyleBoxFlat { BackgroundColor = Color.FromHex("#202025") },
+                PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#202025")},
                 Children =
                 {
-                    new MarginContainer
+                    (_statusContainer = new VBoxContainer
                     {
-                        MarginLeftOverride = 8,
-                        MarginRightOverride = 8,
-                        MarginTopOverride = 4,
-                        MarginBottomOverride = 4,
-                        Children =
-                        {
-                            (_statusContainer = new VBoxContainer())
-                        }
-                    }
+                        Margin = new Thickness(8, 8, 4, 4)
+                    })
                 }
             };
 
             _topContainer.AddChild(topRow);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
-                PanelOverride = new StyleBoxFlat { BackgroundColor = Color.FromHex("#525252ff") }
+                MinSize = (0, 2),
+                PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
             _topContainer.AddChild(middle);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
-                PanelOverride = new StyleBoxFlat { BackgroundColor = Color.FromHex("#525252ff") }
+                MinSize = (0, 2),
+                PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
             CloseButton.OnPressed += _ => Close();
-            LayoutContainer.SetSize(this, (300, 200));
+            SetSize = (300, 200);
         }
 
 
@@ -177,17 +161,19 @@ namespace Content.Client.GameObjects.Components.Atmos
             });
             _statusContainer.AddChild(new Label
             {
-                Text = Loc.GetString("Temperature: {0:0.#}K ({1:0.#}°C)", state.Temperature, TemperatureHelpers.KelvinToCelsius(state.Temperature))
+                Text = Loc.GetString("Temperature: {0:0.#}K ({1:0.#}°C)", state.Temperature,
+                    TemperatureHelpers.KelvinToCelsius(state.Temperature))
             });
             // Return here cause all that stuff down there is gas stuff (so we don't get the seperators)
             if (state.Gases.Length == 0)
             {
                 return;
             }
+
             // Seperator
             _statusContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(0, 10)
+                MinSize = new Vector2(0, 10)
             });
 
             // Add a table with all the gases
@@ -200,7 +186,7 @@ namespace Content.Client.GameObjects.Components.Atmos
                     tableKey,
                     new Control
                     {
-                        CustomMinimumSize = new Vector2(20, 0)
+                        MinSize = new Vector2(20, 0)
                     },
                     tableVal
                 }
@@ -210,13 +196,13 @@ namespace Content.Client.GameObjects.Components.Atmos
             var minSize = 24; // This basically allows gases which are too small, to be shown properly
             var gasBar = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                CustomMinimumSize = new Vector2(0, height)
+                HorizontalExpand = true,
+                MinSize = new Vector2(0, height)
             };
             // Seperator
             _statusContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(0, 10)
+                MinSize = new Vector2(0, 10)
             });
 
             var totalGasAmount = 0f;
@@ -244,8 +230,9 @@ namespace Content.Client.GameObjects.Components.Atmos
                 var right = (i == state.Gases.Length - 1) ? 0f : 2f;
                 gasBar.AddChild(new PanelContainer
                 {
-                    ToolTip = Loc.GetString("{0}: {1:0.##} mol ({2:0.#}%)", gas.Name, gas.Amount, (gas.Amount / totalGasAmount) * 100),
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    ToolTip = Loc.GetString("{0}: {1:0.##} mol ({2:0.#}%)", gas.Name, gas.Amount,
+                        (gas.Amount / totalGasAmount) * 100),
+                    HorizontalExpand = true,
                     SizeFlagsStretchRatio = gas.Amount,
                     MouseFilter = MouseFilterMode.Pass,
                     PanelOverride = new StyleBoxFlat
@@ -254,9 +241,10 @@ namespace Content.Client.GameObjects.Components.Atmos
                         PaddingLeft = left,
                         PaddingRight = right
                     },
-                    CustomMinimumSize = new Vector2(minSize, 0)
+                    MinSize = new Vector2(minSize, 0)
                 });
             }
+
             _statusContainer.AddChild(gasBar);
         }
 
diff --git a/Content.Client/GameObjects/Components/Atmos/GasCanisterWindow.cs b/Content.Client/GameObjects/Components/Atmos/GasCanisterWindow.cs
index c18ae2de0d..50e630db19 100644
--- a/Content.Client/GameObjects/Components/Atmos/GasCanisterWindow.cs
+++ b/Content.Client/GameObjects/Components/Atmos/GasCanisterWindow.cs
@@ -31,10 +31,9 @@ namespace Content.Client.GameObjects.Components.Atmos
 
         public List<ReleasePressureButton> ReleasePressureButtons { get; private set; }
 
-        protected override Vector2? CustomSize => (300, 200);
-
         public GasCanisterWindow()
         {
+            SetSize = MinSize = (300, 200);
             HBoxContainer releasePressureButtons;
 
             Contents.AddChild(new VBoxContainer
@@ -51,7 +50,7 @@ namespace Content.Client.GameObjects.Components.Atmos
                                         {
                                             new Label(){ Text = Loc.GetString("Label: ") },
                                             (LabelInput = new LineEdit() { Text = Name, Editable = false,
-                                                CustomMinimumSize = new Vector2(200, 30)}),
+                                                MinSize = new Vector2(200, 30)}),
                                             (EditLabelBtn = new Button()),
                                         }
                                     },
diff --git a/Content.Client/GameObjects/Components/Body/Scanner/BodyScannerDisplay.cs b/Content.Client/GameObjects/Components/Body/Scanner/BodyScannerDisplay.cs
index 823fb8da7b..1d26c69c37 100644
--- a/Content.Client/GameObjects/Components/Body/Scanner/BodyScannerDisplay.cs
+++ b/Content.Client/GameObjects/Components/Body/Scanner/BodyScannerDisplay.cs
@@ -34,7 +34,7 @@ namespace Content.Client.GameObjects.Components.Body.Scanner
                     // Left half
                     new ScrollContainer
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        HorizontalExpand = true,
                         Children =
                         {
                             (BodyPartList = new ItemList())
@@ -43,13 +43,13 @@ namespace Content.Client.GameObjects.Components.Body.Scanner
                     // Right half
                     new VBoxContainer
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        HorizontalExpand = true,
                         Children =
                         {
                             // Top half of the right half
                             new VBoxContainer
                             {
-                                SizeFlagsVertical = SizeFlags.FillExpand,
+                                VerticalExpand = true,
                                 Children =
                                 {
                                     (BodyPartLabel = new Label()),
@@ -66,7 +66,7 @@ namespace Content.Client.GameObjects.Components.Body.Scanner
                                     },
                                     new ScrollContainer
                                     {
-                                        SizeFlagsVertical = SizeFlags.FillExpand,
+                                        VerticalExpand = true,
                                         Children =
                                         {
                                             (MechanismList = new ItemList())
@@ -77,7 +77,7 @@ namespace Content.Client.GameObjects.Components.Body.Scanner
                             // Bottom half of the right half
                             (MechanismInfoLabel = new RichTextLabel
                             {
-                                SizeFlagsVertical = SizeFlags.FillExpand
+                                VerticalExpand = true
                             })
                         }
                     }
@@ -88,12 +88,11 @@ namespace Content.Client.GameObjects.Components.Body.Scanner
 
             BodyPartList.OnItemSelected += BodyPartOnItemSelected;
             MechanismList.OnItemSelected += MechanismOnItemSelected;
+            MinSize = SetSize = (800, 600);
         }
 
         public BodyScannerBoundUserInterface Owner { get; }
 
-        protected override Vector2? CustomSize => (800, 600);
-
         private ItemList BodyPartList { get; }
 
         private Label BodyPartLabel { get; }
diff --git a/Content.Client/GameObjects/Components/Body/Surgery/SurgeryWindow.cs b/Content.Client/GameObjects/Components/Body/Surgery/SurgeryWindow.cs
index 656aeda4a7..4b428007c8 100644
--- a/Content.Client/GameObjects/Components/Body/Surgery/SurgeryWindow.cs
+++ b/Content.Client/GameObjects/Components/Body/Surgery/SurgeryWindow.cs
@@ -15,10 +15,9 @@ namespace Content.Client.GameObjects.Components.Body.Surgery
         private readonly VBoxContainer _optionsBox;
         private OptionSelectedCallback _optionSelectedCallback;
 
-        protected override Vector2? CustomSize => (300, 400);
-
         public SurgeryWindow()
         {
+            MinSize = SetSize = (300, 400);
             Title = Loc.GetString("Surgery");
             RectClipContent = true;
 
@@ -28,15 +27,15 @@ namespace Content.Client.GameObjects.Components.Body.Surgery
                 {
                     new ScrollContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        VerticalExpand = true,
+                        HorizontalExpand = true,
                         HScrollEnabled = true,
                         VScrollEnabled = true,
                         Children =
                         {
                             (_optionsBox = new VBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand
+                                HorizontalExpand = true
                             })
                         }
                     }
@@ -87,8 +86,8 @@ namespace Content.Client.GameObjects.Components.Body.Surgery
 
             Button = new Button
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 ToggleMode = true,
                 MouseFilter = MouseFilterMode.Stop
             };
@@ -101,16 +100,16 @@ namespace Content.Client.GameObjects.Components.Body.Surgery
                 {
                     (SpriteView = new SpriteView
                     {
-                        CustomMinimumSize = new Vector2(32.0f, 32.0f)
+                        MinSize = new Vector2(32.0f, 32.0f)
                     }),
                     (DisplayText = new Label
                     {
-                        SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                        VerticalAlignment = VAlignment.Center,
                         Text = "N/A",
                     }),
                     (new Control
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     })
                 }
             });
diff --git a/Content.Client/GameObjects/Components/Chemistry/ChemMaster/ChemMasterWindow.cs b/Content.Client/GameObjects/Components/Chemistry/ChemMaster/ChemMasterWindow.cs
index 1c283a4aa7..a688359017 100644
--- a/Content.Client/GameObjects/Components/Chemistry/ChemMaster/ChemMasterWindow.cs
+++ b/Content.Client/GameObjects/Components/Chemistry/ChemMaster/ChemMasterWindow.cs
@@ -47,14 +47,13 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
         public Button CreatePills { get; }
         public Button CreateBottles { get; }
 
-        protected override Vector2? CustomSize => (400, 200);
-
         /// <summary>
         /// Create and initialize the chem master UI client-side. Creates the basic layout,
         /// actual data isn't filled in until the server sends data about the chem master.
         /// </summary>
         public ChemMasterWindow()
         {
+            MinSize = SetSize = (400, 200);
             IoCManager.InjectDependencies(this);
 
             Contents.AddChild(new VBoxContainer
@@ -67,16 +66,16 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                         Children =
                         {
                             new Label {Text = Loc.GetString("Container")},
-                            new Control {SizeFlagsHorizontal = SizeFlags.FillExpand},
+                            new Control {HorizontalExpand = true},
                             (EjectButton = new Button {Text = Loc.GetString("Eject")})
                         }
                     },
                     //Wrap the container info in a PanelContainer so we can color it's background differently.
                     new PanelContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         SizeFlagsStretchRatio = 6,
-                        CustomMinimumSize = (0, 200),
+                        MinSize = (0, 200),
                         PanelOverride = new StyleBoxFlat
                         {
                             BackgroundColor = new Color(27, 27, 30)
@@ -86,7 +85,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                             //Currently empty, when server sends state data this will have container contents and fill volume.
                             (ContainerInfo = new VBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                HorizontalExpand = true,
                                 Children =
                                 {
                                     new Label
@@ -99,7 +98,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                     },
 
                     //Padding
-                    new Control {CustomMinimumSize = (0.0f, 10.0f)},
+                    new Control {MinSize = (0.0f, 10.0f)},
 
                     //Buffer
                     new HBoxContainer
@@ -107,7 +106,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                         Children =
                         {
                             new Label {Text = Loc.GetString("Buffer")},
-                            new Control {SizeFlagsHorizontal = SizeFlags.FillExpand},
+                            new Control {HorizontalExpand = true},
                             (BufferTransferButton = new Button {Text = Loc.GetString("Transfer"), Pressed = BufferModeTransfer, StyleClasses = { StyleBase.ButtonOpenRight }}),
                             (BufferDiscardButton = new Button {Text = Loc.GetString("Discard"), Pressed = !BufferModeTransfer, StyleClasses = { StyleBase.ButtonOpenLeft }})
                         }
@@ -116,9 +115,9 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                     //Wrap the buffer info in a PanelContainer so we can color it's background differently.
                     new PanelContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         SizeFlagsStretchRatio = 6,
-                        CustomMinimumSize = (0, 100),
+                        MinSize = (0, 100),
                         PanelOverride = new StyleBoxFlat
                         {
                             BackgroundColor = new Color(27, 27, 30)
@@ -128,7 +127,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                             //Buffer reagent list
                             (BufferInfo = new VBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                HorizontalExpand = true,
                                 Children =
                                 {
                                     new Label
@@ -141,7 +140,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                     },
 
                     //Padding
-                    new Control {CustomMinimumSize = (0.0f, 10.0f)},
+                    new Control {MinSize = (0.0f, 10.0f)},
 
                     //Packaging
                     new HBoxContainer
@@ -155,9 +154,9 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                     //Wrap the packaging info in a PanelContainer so we can color it's background differently.
                     new PanelContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         SizeFlagsStretchRatio = 6,
-                        CustomMinimumSize = (0, 100),
+                        MinSize = (0, 100),
                         PanelOverride = new StyleBoxFlat
                         {
                             BackgroundColor = new Color(27, 27, 30)
@@ -167,7 +166,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                             //Packaging options
                             (PackagingInfo = new VBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                HorizontalExpand = true,
                             }),
 
                         }
@@ -190,12 +189,12 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
             };
             PackagingInfo.AddChild(PillInfo);
 
-            var pillPadding = new Control {SizeFlagsHorizontal = SizeFlags.FillExpand};
+            var pillPadding = new Control {HorizontalExpand = true};
             PillInfo.AddChild(pillPadding);
 
             PillAmount = new SpinBox
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 Value = 1
             };
             PillAmount.InitDefaultButtons();
@@ -227,12 +226,12 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
             };
             PackagingInfo.AddChild(BottleInfo);
 
-            var bottlePadding = new Control {SizeFlagsHorizontal = SizeFlags.FillExpand};
+            var bottlePadding = new Control {HorizontalExpand = true};
             BottleInfo.AddChild(bottlePadding);
 
             BottleAmount = new SpinBox
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 Value = 1
             };
             BottleAmount.InitDefaultButtons();
@@ -351,7 +350,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                             },
 
                             //Padding
-                            new Control {SizeFlagsHorizontal = SizeFlags.FillExpand},
+                            new Control {HorizontalExpand = true},
 
                             MakeChemButton("1", ReagentUnit.New(1), reagent.ReagentId, false, StyleBase.ButtonOpenRight),
                             MakeChemButton("5", ReagentUnit.New(5), reagent.ReagentId, false, StyleBase.ButtonOpenBoth),
@@ -407,7 +406,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ChemMaster
                             },
 
                             //Padding
-                            new Control {SizeFlagsHorizontal = SizeFlags.FillExpand},
+                            new Control {HorizontalExpand = true},
 
                             MakeChemButton("1", ReagentUnit.New(1), reagent.ReagentId, true, StyleBase.ButtonOpenRight),
                             MakeChemButton("5", ReagentUnit.New(5), reagent.ReagentId, true, StyleBase.ButtonOpenBoth),
diff --git a/Content.Client/GameObjects/Components/Chemistry/ReagentDispenser/ReagentDispenserWindow.cs b/Content.Client/GameObjects/Components/Chemistry/ReagentDispenser/ReagentDispenserWindow.cs
index 8f8c35c5d6..773a54238b 100644
--- a/Content.Client/GameObjects/Components/Chemistry/ReagentDispenser/ReagentDispenserWindow.cs
+++ b/Content.Client/GameObjects/Components/Chemistry/ReagentDispenser/ReagentDispenserWindow.cs
@@ -61,14 +61,13 @@ namespace Content.Client.GameObjects.Components.Chemistry.ReagentDispenser
         /// <summary>A grid of buttons for each reagent which can be dispensed.</summary>
         public GridContainer ChemicalList { get; }
 
-        protected override Vector2? CustomSize => (500, 600);
-
         /// <summary>
         /// Create and initialize the dispenser UI client-side. Creates the basic layout,
         /// actual data isn't filled in until the server sends data about the dispenser.
         /// </summary>
         public ReagentDispenserWindow()
         {
+            SetSize = MinSize = (500, 600);
             IoCManager.InjectDependencies(this);
 
             var dispenseAmountGroup = new ButtonGroup();
@@ -84,7 +83,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ReagentDispenser
                         {
                             new Label {Text = Loc.GetString("Amount")},
                             //Padding
-                            new Control {CustomMinimumSize = (20, 0)},
+                            new Control {MinSize = (20, 0)},
                             (DispenseButton1 = new Button {Text = "1", Group = dispenseAmountGroup, StyleClasses = { StyleBase.ButtonOpenRight }}),
                             (DispenseButton5 = new Button {Text = "5", Group = dispenseAmountGroup, StyleClasses = { StyleBase.ButtonOpenBoth }}),
                             (DispenseButton10 = new Button {Text = "10", Group = dispenseAmountGroup, StyleClasses = { StyleBase.ButtonOpenBoth }}),
@@ -97,14 +96,14 @@ namespace Content.Client.GameObjects.Components.Chemistry.ReagentDispenser
                         }
                     },
                     //Padding
-                    new Control {CustomMinimumSize = (0.0f, 10.0f)},
+                    new Control {MinSize = (0.0f, 10.0f)},
                     //Grid of which reagents can be dispensed.
                     (ChemicalList = new GridContainer
                     {
                         Columns = 5
                     }),
                     //Padding
-                    new Control {CustomMinimumSize = (0.0f, 10.0f)},
+                    new Control {MinSize = (0.0f, 10.0f)},
                     new HBoxContainer
                     {
                         Children =
@@ -117,9 +116,9 @@ namespace Content.Client.GameObjects.Components.Chemistry.ReagentDispenser
                     //Wrap the container info in a PanelContainer so we can color it's background differently.
                     new PanelContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         SizeFlagsStretchRatio = 6,
-                        CustomMinimumSize = (0, 150),
+                        MinSize = (0, 150),
                         PanelOverride = new StyleBoxFlat
                         {
                             BackgroundColor = new Color(27, 27, 30)
@@ -129,7 +128,7 @@ namespace Content.Client.GameObjects.Components.Chemistry.ReagentDispenser
                             //Currently empty, when server sends state data this will have container contents and fill volume.
                             (ContainerInfo = new VBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                HorizontalExpand = true,
                                 Children =
                                 {
                                     new Label
diff --git a/Content.Client/GameObjects/Components/CloningPod/CloningPodWindow.cs b/Content.Client/GameObjects/Components/CloningPod/CloningPodWindow.cs
index 2cf858a5d0..9be78d069b 100644
--- a/Content.Client/GameObjects/Components/CloningPod/CloningPodWindow.cs
+++ b/Content.Client/GameObjects/Components/CloningPod/CloningPodWindow.cs
@@ -1,5 +1,4 @@
 #nullable enable
-using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using Robust.Client.UserInterface;
@@ -7,8 +6,6 @@ using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
 using Robust.Shared.Localization;
 using Robust.Shared.Maths;
-using Robust.Shared.Timing;
-using Robust.Shared.Utility;
 using static Content.Shared.GameObjects.Components.Medical.SharedCloningPodComponent;
 
 namespace Content.Client.GameObjects.Components.CloningPod
@@ -17,68 +14,36 @@ namespace Content.Client.GameObjects.Components.CloningPod
     {
         private Dictionary<int, string> _scanManager;
 
-        private readonly VBoxContainer _mainVBox;
-        private readonly ScanListContainer _scanList;
-        private readonly LineEdit _searchBar;
-        private readonly Button _clearButton;
+        private readonly VBoxContainer _scanList;
         public readonly Button CloneButton;
         public readonly Button EjectButton;
-        private readonly CloningScanButton _measureButton;
         private CloningScanButton? _selectedButton;
         private readonly Label _progressLabel;
         private readonly ProgressBar _cloningProgressBar;
         private readonly Label _mindState;
 
-        protected override Vector2 ContentsMinimumSize => _mainVBox?.CombinedMinimumSize ?? Vector2.Zero;
         private CloningPodBoundUserInterfaceState _lastUpdate = null!;
 
-        // List of scans that are visible based on current filter criteria.
-        private readonly Dictionary<int, string> _filteredScans = new();
-
-        // The indices of the visible scans last time UpdateVisibleScans was ran.
-        // This is inclusive, so end is the index of the last scan, not right after it.
-        private (int start, int end) _lastScanIndices;
-
         public int? SelectedScan;
 
-        protected override Vector2? CustomSize => (250, 300);
-
-        public CloningPodWindow(
-            Dictionary<int, string> scanManager)
+        public CloningPodWindow(Dictionary<int, string> scanManager)
         {
+            SetSize = MinSize = (250, 300);
             _scanManager = scanManager;
 
-
             Title = Loc.GetString("Cloning Machine");
 
-            Contents.AddChild(_mainVBox = new VBoxContainer
+            Contents.AddChild(new VBoxContainer
             {
                 Children =
                 {
-                    new HBoxContainer
-                    {
-                        Children =
-                        {
-                            (_searchBar = new LineEdit
-                            {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                PlaceHolder = Loc.GetString("Search")
-                            }),
-
-                            (_clearButton = new Button
-                            {
-                                Disabled = true,
-                                Text = Loc.GetString("Clear"),
-                            })
-                        }
-                    },
                     new ScrollContainer
                     {
-                        CustomMinimumSize = new Vector2(200.0f, 0.0f),
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        MinSize = new Vector2(200.0f, 0.0f),
+                        VerticalExpand = true,
                         Children =
                         {
-                            (_scanList = new ScanListContainer())
+                            (_scanList = new VBoxContainer())
                         }
                     },
                     new VBoxContainer
@@ -91,11 +56,9 @@ namespace Content.Client.GameObjects.Components.CloningPod
                             })
                         }
                     },
-                    (_measureButton = new CloningScanButton {Visible = false}),
                     (_cloningProgressBar = new ProgressBar
                     {
-                        CustomMinimumSize = (200, 20),
-                        SizeFlagsHorizontal = SizeFlags.Fill,
+                        MinSize = (200, 20),
                         MinValue = 0,
                         MaxValue = 10,
                         Page = 0,
@@ -127,13 +90,7 @@ namespace Content.Client.GameObjects.Components.CloningPod
                 }
             });
 
-
-            _searchBar.OnTextChanged += OnSearchBarTextChanged;
-            _clearButton.OnPressed += OnClearButtonPressed;
-
-            BuildEntityList();
-
-            _searchBar.GrabKeyboardFocus();
+            BuildCloneList();
         }
 
         public void Populate(CloningPodBoundUserInterfaceState state)
@@ -143,7 +100,7 @@ namespace Content.Client.GameObjects.Components.CloningPod
             if (_lastUpdate == null || _lastUpdate.MindIdName.Count != state.MindIdName.Count)
             {
                 _scanManager = state.MindIdName;
-                BuildEntityList();
+                BuildCloneList();
                 _lastUpdate = state;
             }
 
@@ -155,130 +112,31 @@ namespace Content.Client.GameObjects.Components.CloningPod
             _mindState.FontColorOverride = state.MindPresent ? Color.Green : Color.Red;
         }
 
-        private void OnSearchBarTextChanged(LineEdit.LineEditEventArgs args)
+        private void BuildCloneList()
         {
-            BuildEntityList(args.Text);
-            _clearButton.Disabled = string.IsNullOrEmpty(args.Text);
-        }
-
-        private void OnClearButtonPressed(BaseButton.ButtonEventArgs args)
-        {
-            _searchBar.Clear();
-            BuildEntityList("");
-        }
-
-
-        private void BuildEntityList(string? searchStr = null)
-        {
-            _filteredScans.Clear();
-            _scanList.RemoveAllChildren();
-            // Reset last scan indices so it automatically updates the entire list.
-            _lastScanIndices = (0, -1);
             _scanList.RemoveAllChildren();
             _selectedButton = null;
-            searchStr = searchStr?.ToLowerInvariant();
 
             foreach (var scan in _scanManager)
             {
-                if (searchStr != null && !_doesScanMatchSearch(scan.Value, searchStr))
+                var button = new CloningScanButton
                 {
-                    continue;
+                    Scan = scan.Value,
+                    Id = scan.Key
+                };
+                button.ActualButton.OnToggled += OnItemButtonToggled;
+                var entityLabelText = scan.Value;
+
+                button.EntityLabel.Text = entityLabelText;
+
+                if (scan.Key == SelectedScan)
+                {
+                    _selectedButton = button;
+                    _selectedButton.ActualButton.Pressed = true;
                 }
 
-                _filteredScans.Add(scan.Key, scan.Value);
-            }
-
-            //TODO: set up sort
-            //_filteredScans.Sort((a, b) => string.Compare(a.ToString(), b.ToString(), StringComparison.Ordinal));
-
-            _scanList.TotalItemCount = _filteredScans.Count;
-        }
-
-        private void UpdateVisibleScans()
-        {
-            // Update visible buttons in the scan list.
-
-            // Calculate index of first scan to render based on current scroll.
-            var height = _measureButton.CombinedMinimumSize.Y + ScanListContainer.Separation;
-            var offset = -_scanList.Position.Y;
-            var startIndex = (int) Math.Floor(offset / height);
-            _scanList.ItemOffset = startIndex;
-
-            var (prevStart, prevEnd) = _lastScanIndices;
-
-            // Calculate index of final one.
-            var endIndex = startIndex - 1;
-            var spaceUsed = -height; // -height instead of 0 because else it cuts off the last button.
-
-            while (spaceUsed < _scanList.Parent!.Height)
-            {
-                spaceUsed += height;
-                endIndex += 1;
-            }
-
-            endIndex = Math.Min(endIndex, _filteredScans.Count - 1);
-
-            if (endIndex == prevEnd && startIndex == prevStart)
-            {
-                // Nothing changed so bye.
-                return;
-            }
-
-            _lastScanIndices = (startIndex, endIndex);
-
-            // Delete buttons at the start of the list that are no longer visible (scrolling down).
-            for (var i = prevStart; i < startIndex && i <= prevEnd; i++)
-            {
-                var control = (CloningScanButton) _scanList.GetChild(0);
-                DebugTools.Assert(control.Index == i);
-                _scanList.RemoveChild(control);
-            }
-
-            // Delete buttons at the end of the list that are no longer visible (scrolling up).
-            for (var i = prevEnd; i > endIndex && i >= prevStart; i--)
-            {
-                var control = (CloningScanButton) _scanList.GetChild(_scanList.ChildCount - 1);
-                DebugTools.Assert(control.Index == i);
-                _scanList.RemoveChild(control);
-            }
-
-            var array = _filteredScans.ToArray();
-
-            // Create buttons at the start of the list that are now visible (scrolling up).
-            for (var i = Math.Min(prevStart - 1, endIndex); i >= startIndex; i--)
-            {
-                InsertEntityButton(array[i], true, i);
-            }
-
-            // Create buttons at the end of the list that are now visible (scrolling down).
-            for (var i = Math.Max(prevEnd + 1, startIndex); i <= endIndex; i++)
-            {
-                InsertEntityButton(array[i], false, i);
-            }
-        }
-
-        // Create a spawn button and insert it into the start or end of the list.
-        private void InsertEntityButton(KeyValuePair<int, string> scan, bool insertFirst, int index)
-        {
-            var button = new CloningScanButton
-            {
-                Scan = scan.Value,
-                Id = scan.Key,
-                Index = index // We track this index purely for debugging.
-            };
-            button.ActualButton.OnToggled += OnItemButtonToggled;
-            var entityLabelText = scan.Value;
-
-            button.EntityLabel.Text = entityLabelText;
-
-            if (scan.Key == SelectedScan)
-            {
-                _selectedButton = button;
-                _selectedButton.ActualButton.Pressed = true;
-            }
-
-            //TODO: replace with body's face
-            /*var tex = IconComponent.GetScanIcon(scan, resourceCache);
+                //TODO: replace with body's face
+                /*var tex = IconComponent.GetScanIcon(scan, resourceCache);
             var rect = button.EntityTextureRect;
             if (tex != null)
             {
@@ -292,16 +150,11 @@ namespace Content.Client.GameObjects.Components.CloningPod
             rect.Dispose();
             */
 
-            _scanList.AddChild(button);
-            if (insertFirst)
-            {
-                button.SetPositionInParent(0);
+                _scanList.AddChild(button);
             }
-        }
 
-        private static bool _doesScanMatchSearch(string scan, string searchStr)
-        {
-            return scan.ToLowerInvariant().Contains(searchStr);
+            //TODO: set up sort
+            //_filteredScans.Sort((a, b) => string.Compare(a.ToString(), b.ToString(), StringComparison.Ordinal));
         }
 
         private void OnItemButtonToggled(BaseButton.ButtonToggledEventArgs args)
@@ -325,76 +178,6 @@ namespace Content.Client.GameObjects.Components.CloningPod
             SelectedScan = item.Id;
         }
 
-        protected override void FrameUpdate(FrameEventArgs args)
-        {
-            base.FrameUpdate(args);
-            UpdateVisibleScans();
-        }
-
-        private class ScanListContainer : Container
-        {
-            // Quick and dirty container to do virtualization of the list.
-            // Basically, get total item count and offset to put the current buttons at.
-            // Get a constant minimum height and move the buttons in the list up to match the scrollbar.
-            private int _totalItemCount;
-            private int _itemOffset;
-
-            public int TotalItemCount
-            {
-                get => _totalItemCount;
-                set
-                {
-                    _totalItemCount = value;
-                    MinimumSizeChanged();
-                }
-            }
-
-            public int ItemOffset
-            {
-                get => _itemOffset;
-                set
-                {
-                    _itemOffset = value;
-                    UpdateLayout();
-                }
-            }
-
-            public const float Separation = 2;
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                if (ChildCount == 0)
-                {
-                    return Vector2.Zero;
-                }
-
-                var first = GetChild(0);
-
-                var (minX, minY) = first.CombinedMinimumSize;
-
-                return (minX, minY * TotalItemCount + (TotalItemCount - 1) * Separation);
-            }
-
-            protected override void LayoutUpdateOverride()
-            {
-                if (ChildCount == 0)
-                {
-                    return;
-                }
-
-                var first = GetChild(0);
-
-                var height = first.CombinedMinimumSize.Y;
-                var offset = ItemOffset * height + (ItemOffset - 1) * Separation;
-
-                foreach (var child in Children)
-                {
-                    FitChildInBox(child, UIBox2.FromDimensions(0, offset, Width, height));
-                    offset += Separation + height;
-                }
-            }
-        }
-
         [DebuggerDisplay("cloningbutton {" + nameof(Index) + "}")]
         private class CloningScanButton : Control
         {
@@ -409,8 +192,8 @@ namespace Content.Client.GameObjects.Components.CloningPod
             {
                 AddChild(ActualButton = new Button
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
+                    VerticalExpand = true,
                     ToggleMode = true,
                 });
 
@@ -420,16 +203,16 @@ namespace Content.Client.GameObjects.Components.CloningPod
                     {
                         (EntityTextureRect = new TextureRect
                         {
-                            CustomMinimumSize = (32, 32),
-                            SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                            MinSize = (32, 32),
+                            HorizontalAlignment = HAlignment.Center,
+                            VerticalAlignment = VAlignment.Center,
                             Stretch = TextureRect.StretchMode.KeepAspectCentered,
                             CanShrink = true
                         }),
                         (EntityLabel = new Label
                         {
-                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            VerticalAlignment = VAlignment.Center,
+                            HorizontalExpand = true,
                             Text = "",
                             ClipText = true
                         })
diff --git a/Content.Client/GameObjects/Components/Configuration/ConfigurationMenu.cs b/Content.Client/GameObjects/Components/Configuration/ConfigurationMenu.cs
index 6e0b65d9a2..22886b426b 100644
--- a/Content.Client/GameObjects/Components/Configuration/ConfigurationMenu.cs
+++ b/Content.Client/GameObjects/Components/Configuration/ConfigurationMenu.cs
@@ -19,80 +19,52 @@ namespace Content.Client.GameObjects.Components.Wires
 
         private readonly List<(string  name, LineEdit input)> _inputs;
 
-        protected override Vector2? CustomSize => (300, 250);
-
         public ConfigurationMenu(ConfigurationBoundUserInterface owner)
         {
+            MinSize = SetSize = (300, 250);
             Owner = owner;
 
             _inputs = new List<(string name, LineEdit input)>();
 
             Title = Loc.GetString("Device Configuration");
 
-            var margin = new MarginContainer
-            {
-                MarginBottomOverride = 8,
-                MarginLeftOverride = 8,
-                MarginRightOverride = 8,
-                MarginTopOverride = 8
-            };
-
             _baseContainer = new VBoxContainer
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                VerticalExpand = true,
+                HorizontalExpand = true
             };
 
             _column = new VBoxContainer
             {
+                Margin = new Thickness(8),
                 SeparationOverride = 16,
-                SizeFlagsVertical = SizeFlags.Fill
             };
 
             _row = new HBoxContainer
             {
                 SeparationOverride = 16,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
-            };
-
-            var buttonRow = new HBoxContainer
-            {
-                SizeFlagsHorizontal = SizeFlags.FillExpand
-            };
-
-            var spacer1 = new HBoxContainer
-            {
-                SizeFlagsHorizontal = SizeFlags.Expand
-            };
-
-            var spacer2 = new HBoxContainer()
-            {
-                SizeFlagsHorizontal = SizeFlags.Expand
+                HorizontalExpand = true
             };
 
             var confirmButton = new Button
             {
                 Text = Loc.GetString("Confirm"),
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center
             };
 
             confirmButton.OnButtonUp += OnConfirm;
-            buttonRow.AddChild(spacer1);
-            buttonRow.AddChild(confirmButton);
-            buttonRow.AddChild(spacer2);
 
             var outerColumn = new ScrollContainer
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                VerticalExpand = true,
+                HorizontalExpand = true,
                 ModulateSelfOverride = Color.FromHex("#202025")
             };
 
-            margin.AddChild(_column);
-            outerColumn.AddChild(margin);
+            outerColumn.AddChild(_column);
             _baseContainer.AddChild(outerColumn);
-            _baseContainer.AddChild(buttonRow);
+            _baseContainer.AddChild(confirmButton);
             Contents.AddChild(_baseContainer);
         }
 
@@ -103,19 +75,15 @@ namespace Content.Client.GameObjects.Components.Wires
 
             foreach (var field in state.Config)
             {
-                var margin = new MarginContainer
-                {
-                    MarginRightOverride = 8
-                };
-
                 var label = new Label
                 {
+                    Margin = new Thickness(0, 0, 8, 0),
                     Name = field.Key,
                     Text = field.Key + ":",
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalAlignment = VAlignment.Center,
+                    HorizontalExpand = true,
                     SizeFlagsStretchRatio = .2f,
-                    CustomMinimumSize = new Vector2(60, 0)
+                    MinSize = new Vector2(60, 0)
                 };
 
                 var input = new LineEdit
@@ -123,7 +91,7 @@ namespace Content.Client.GameObjects.Components.Wires
                     Name = field.Key + "-input",
                     Text = field.Value,
                     IsValid = Validate,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     SizeFlagsStretchRatio = .8f
                 };
 
@@ -132,8 +100,7 @@ namespace Content.Client.GameObjects.Components.Wires
                 var row = new HBoxContainer();
                 CopyProperties(_row, row);
 
-                margin.AddChild(label);
-                row.AddChild(margin);
+                row.AddChild(label);
                 row.AddChild(input);
                 _column.AddChild(row);
             }
diff --git a/Content.Client/GameObjects/Components/Crayon/CrayonWindow.cs b/Content.Client/GameObjects/Components/Crayon/CrayonWindow.cs
index 347c93cd3e..b7d8c22aeb 100644
--- a/Content.Client/GameObjects/Components/Crayon/CrayonWindow.cs
+++ b/Content.Client/GameObjects/Components/Crayon/CrayonWindow.cs
@@ -20,10 +20,9 @@ namespace Content.Client.GameObjects.Components.Crayon
         private string _selected;
         private Color _color;
 
-        protected override Vector2? CustomSize => (250, 300);
-
         public CrayonWindow(CrayonBoundUserInterface owner)
         {
+            MinSize = SetSize = (250, 300);
             Title = Loc.GetString("Crayon");
             Owner = owner;
 
@@ -40,7 +39,7 @@ namespace Content.Client.GameObjects.Components.Crayon
             };
             var gridScroll = new ScrollContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 Children =
                 {
                     _grid
@@ -115,7 +114,7 @@ namespace Content.Client.GameObjects.Components.Crayon
                 var rsi = new SpriteSpecifier.Rsi(path, state);
                 _decals.Add(state, rsi.Frame0());
             }
-            
+
             RefreshList();
         }
     }
diff --git a/Content.Client/GameObjects/Components/Disposal/DisposalMailingUnitWindow.cs b/Content.Client/GameObjects/Components/Disposal/DisposalMailingUnitWindow.cs
index 41b528ad10..d2f8d3138c 100644
--- a/Content.Client/GameObjects/Components/Disposal/DisposalMailingUnitWindow.cs
+++ b/Content.Client/GameObjects/Components/Disposal/DisposalMailingUnitWindow.cs
@@ -26,189 +26,167 @@ namespace Content.Client.GameObjects.Components.Disposal
         public List<string> TargetList;
         private readonly Label _tagLabel;
 
-        protected override Vector2? CustomSize => (460, 220);
-
         public DisposalMailingUnitWindow()
         {
+            MinSize = SetSize = (460, 220);
             TargetList = new List<string>();
             Contents.AddChild(new HBoxContainer
             {
                 Children =
                 {
-                    new MarginContainer
+                    new VBoxContainer
                     {
-                        MarginLeftOverride = 8,
-                        MarginRightOverride = 8,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        HorizontalExpand = true,
+                        Margin = new Thickness(8, 0),
                         Children =
                         {
-                            new VBoxContainer
+                            new HBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
                                 Children =
                                 {
-                                    new HBoxContainer
+                                    new Label {Text = Loc.GetString("State: ")},
+                                    new Control {MinSize = (4, 0)},
+                                    (_unitState = new Label {Text = Loc.GetString("Ready")})
+                                }
+                            },
+                            new Control {MinSize = (0, 10)},
+                            new HBoxContainer
+                            {
+                                HorizontalExpand = true,
+                                Children =
+                                {
+                                    new Label {Text = Loc.GetString("Pressure:")},
+                                    new Control {MinSize = (4, 0)},
+                                    (_pressureBar = new ProgressBar
                                     {
+                                        MinSize = (100, 20),
+                                        HorizontalExpand = true,
+                                        MinValue = 0,
+                                        MaxValue = 1,
+                                        Page = 0,
+                                        Value = 0.5f,
                                         Children =
                                         {
-                                            new Label {Text = Loc.GetString("State: ")},
-                                            new Control {CustomMinimumSize = (4, 0)},
-                                            (_unitState = new Label {Text = Loc.GetString("Ready")})
+                                            (_pressurePercentage = new Label())
                                         }
+                                    })
+                                }
+                            },
+                            new Control {MinSize = (0, 10)},
+                            new HBoxContainer
+                            {
+                                HorizontalExpand = true,
+                                Children =
+                                {
+                                    new Label {Text = Loc.GetString("Handle:")},
+                                    new Control
+                                    {
+                                        MinSize = (4, 0),
+                                        HorizontalExpand = true
                                     },
-                                    new Control {CustomMinimumSize = (0, 10)},
-                                    new HBoxContainer
+                                    (Engage = new Button
                                     {
-                                        SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                        Children =
-                                        {
-                                            new Label {Text = Loc.GetString("Pressure:")},
-                                            new Control {CustomMinimumSize = (4, 0)},
-                                            (_pressureBar = new ProgressBar
-                                            {
-                                                CustomMinimumSize = (100, 20),
-                                                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                                MinValue = 0,
-                                                MaxValue = 1,
-                                                Page = 0,
-                                                Value = 0.5f,
-                                                Children =
-                                                {
-                                                    (_pressurePercentage = new Label())
-                                                }
-                                            })
-                                        }
+                                        MinSize = (16, 0),
+                                        Text = Loc.GetString("Engage"),
+                                        ToggleMode = true,
+                                        Disabled = true
+                                    })
+                                }
+                            },
+                            new Control {MinSize = (0, 10)},
+                            new HBoxContainer
+                            {
+                                HorizontalExpand = true,
+                                Children =
+                                {
+                                    new Label {Text = Loc.GetString("Eject:")},
+                                    new Control
+                                    {
+                                        MinSize = (4, 0),
+                                        HorizontalExpand = true
                                     },
-                                    new Control {CustomMinimumSize = (0, 10)},
-                                    new HBoxContainer
+                                    (Eject = new Button
                                     {
-                                        SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                        Children =
-                                        {
-                                            new Label {Text = Loc.GetString("Handle:")},
-                                            new Control {
-                                                CustomMinimumSize = (4, 0),
-                                                SizeFlagsHorizontal = SizeFlags.FillExpand
-                                            },
-                                            (Engage = new Button
-                                            {
-                                                CustomMinimumSize = (16, 0),
-                                                Text = Loc.GetString("Engage"),
-                                                ToggleMode = true,
-                                                Disabled = true
-                                            })
-                                        }
-                                    },
-                                    new Control {CustomMinimumSize = (0, 10)},
-                                    new HBoxContainer
+                                        MinSize = (16, 0),
+                                        Text = Loc.GetString("Eject Contents"),
+                                        //HorizontalAlignment = HAlignment.Right
+                                    })
+                                }
+                            },
+                            new Control {MinSize = (0, 10)},
+                            new HBoxContainer
+                            {
+                                Children =
+                                {
+                                    (Power = new CheckButton {Text = Loc.GetString("Power")}),
+                                }
+                            }
+                        }
+                    },
+                    new VBoxContainer
+                    {
+                        Margin = new Thickness(12, 0, 8, 0),
+                        Children =
+                        {
+                            new HBoxContainer
+                            {
+                                Children =
+                                {
+                                    new Label
                                     {
-                                        SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                        Children =
-                                        {
-                                            new Label {Text = Loc.GetString("Eject:")},
-                                            new Control {
-                                                CustomMinimumSize = (4, 0),
-                                                SizeFlagsHorizontal = SizeFlags.FillExpand
-                                            },
-                                            (Eject = new Button {
-                                                CustomMinimumSize = (16, 0),
-                                                Text = Loc.GetString("Eject Contents"),
-                                                //SizeFlagsHorizontal = SizeFlags.ShrinkEnd
-                                            })
-                                        }
-                                    },
-                                    new Control {CustomMinimumSize = (0, 10)},
-                                    new HBoxContainer
-                                    {
-                                        Children =
-                                        {
-                                            (Power = new CheckButton {Text = Loc.GetString("Power")}),
-                                        }
+                                        Text = Loc.GetString("Select a destination:")
                                     }
                                 }
                             },
-                        }
-                    },
-                    new MarginContainer
-                    {
-                        MarginLeftOverride = 12,
-                        MarginRightOverride = 8,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
-                        Children =
-                        {
-                            new VBoxContainer
+                            new Control {MinSize = new Vector2(0, 8)},
+                            new HBoxContainer
                             {
-                                SizeFlagsHorizontal = SizeFlags.Fill,
+                                VerticalExpand = true,
                                 Children =
                                 {
-                                    new HBoxContainer
+                                    (TargetListContainer = new ItemList
+                                    {
+                                        SelectMode = ItemList.ItemListSelectMode.Single,
+                                        HorizontalExpand = true,
+                                        VerticalExpand = true
+                                    })
+                                }
+                            },
+                            new PanelContainer
+                            {
+                                PanelOverride = new StyleBoxFlat
+                                {
+                                    BackgroundColor = Color.FromHex("#ACBDBA")
+                                },
+                                HorizontalExpand = true,
+                                MinSize = new Vector2(0, 1),
+                            },
+                            new HBoxContainer
+                            {
+                                Children =
+                                {
+                                    new VBoxContainer
                                     {
                                         Children =
                                         {
-                                            new Label
-                                            {
-                                                Text = Loc.GetString("Select a destination:")
-                                            }
-                                        }
-                                    },
-                                    new Control { CustomMinimumSize = new Vector2(0, 8) },
-                                    new HBoxContainer
-                                    {
-                                        SizeFlagsVertical = SizeFlags.FillExpand,
-                                        Children =
-                                        {
-                                            (TargetListContainer = new ItemList
-                                            {
-                                                SelectMode = ItemList.ItemListSelectMode.Single,
-                                                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                                SizeFlagsVertical = SizeFlags.FillExpand
-                                            })
-                                        }
-                                    },
-                                    new PanelContainer
-                                    {
-                                        PanelOverride = new StyleBoxFlat
-                                        {
-                                            BackgroundColor = Color.FromHex("#ACBDBA")
-                                        },
-                                        SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                        CustomMinimumSize = new Vector2(0, 1),
-                                    },
-                                    new HBoxContainer
-                                    {
-                                        Children =
-                                        {
-                                            new VBoxContainer
+                                            new HBoxContainer
                                             {
+                                                Margin = new Thickness(4, 0, 0, 0),
                                                 Children =
                                                 {
-                                                    new MarginContainer
+                                                    new Label
                                                     {
-                                                        MarginLeftOverride = 4,
-                                                        Children =
-                                                        {
-                                                            new HBoxContainer
-                                                            {
-                                                                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                                                                Children =
-                                                                {
-                                                                    new Label
-                                                                    {
-                                                                        Text = Loc.GetString("This unit:")
-                                                                    },
-                                                                    new Control
-                                                                    {
-                                                                        CustomMinimumSize = new Vector2(4, 0)
-                                                                    },
-                                                                    (_tagLabel = new Label
-                                                                    {
-                                                                        Text = "-",
-                                                                        SizeFlagsVertical = SizeFlags.ShrinkEnd
-                                                                    })
-                                                                }
-                                                            }
-                                                        }
+                                                        Text = Loc.GetString("This unit:")
                                                     },
+                                                    new Control
+                                                    {
+                                                        MinSize = new Vector2(4, 0)
+                                                    },
+                                                    (_tagLabel = new Label
+                                                    {
+                                                        Text = "-",
+                                                        VerticalAlignment = VAlignment.Bottom
+                                                    })
                                                 }
                                             }
                                         }
diff --git a/Content.Client/GameObjects/Components/Disposal/DisposalRouterWindow.cs b/Content.Client/GameObjects/Components/Disposal/DisposalRouterWindow.cs
index 98e345f124..45f5f9deaf 100644
--- a/Content.Client/GameObjects/Components/Disposal/DisposalRouterWindow.cs
+++ b/Content.Client/GameObjects/Components/Disposal/DisposalRouterWindow.cs
@@ -16,10 +16,9 @@ namespace Content.Client.GameObjects.Components.Disposal
         public readonly LineEdit TagInput;
         public readonly Button Confirm;
 
-        protected override Vector2? CustomSize => (400, 80);
-
         public DisposalRouterWindow()
         {
+            MinSize = SetSize = (400, 80);
             Title = Loc.GetString("Disposal Router");
 
             Contents.AddChild(new VBoxContainer
@@ -27,14 +26,19 @@ namespace Content.Client.GameObjects.Components.Disposal
                 Children =
                 {
                     new Label {Text = Loc.GetString("Tags:")},
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
                         {
-                            (TagInput = new LineEdit {SizeFlagsHorizontal = SizeFlags.Expand, CustomMinimumSize = (320, 0),
-                                ToolTip = Loc.GetString("A comma separated list of tags"), IsValid = tags => TagRegex.IsMatch(tags)}),
-                            new Control {CustomMinimumSize = (10, 0)},
+                            (TagInput = new LineEdit
+                            {
+                                HorizontalExpand = true,
+                                MinSize = (320, 0),
+                                ToolTip = Loc.GetString("A comma separated list of tags"),
+                                IsValid = tags => TagRegex.IsMatch(tags)
+                            }),
+                            new Control {MinSize = (10, 0)},
                             (Confirm = new Button {Text = Loc.GetString("Confirm")})
                         }
                     }
diff --git a/Content.Client/GameObjects/Components/Disposal/DisposalTaggerWindow.cs b/Content.Client/GameObjects/Components/Disposal/DisposalTaggerWindow.cs
index 54dec5b807..9275127a59 100644
--- a/Content.Client/GameObjects/Components/Disposal/DisposalTaggerWindow.cs
+++ b/Content.Client/GameObjects/Components/Disposal/DisposalTaggerWindow.cs
@@ -16,10 +16,9 @@ namespace Content.Client.GameObjects.Components.Disposal
         public readonly LineEdit TagInput;
         public readonly Button Confirm;
 
-        protected override Vector2? CustomSize => (400, 80);
-
         public DisposalTaggerWindow()
         {
+            MinSize = SetSize = (400, 80);
             Title = Loc.GetString("Disposal Tagger");
 
             Contents.AddChild(new VBoxContainer
@@ -27,14 +26,18 @@ namespace Content.Client.GameObjects.Components.Disposal
                 Children =
                 {
                     new Label {Text = Loc.GetString("Tag:")},
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
                         {
-                            (TagInput = new LineEdit {SizeFlagsHorizontal = SizeFlags.Expand, CustomMinimumSize = (320, 0),
-                                IsValid = tag => TagRegex.IsMatch(tag)}),
-                            new Control {CustomMinimumSize = (10, 0)},
+                            (TagInput = new LineEdit
+                            {
+                                HorizontalExpand = true,
+                                MinSize = (320, 0),
+                                IsValid = tag => TagRegex.IsMatch(tag)
+                            }),
+                            new Control {MinSize = (10, 0)},
                             (Confirm = new Button {Text = Loc.GetString("Confirm")})
                         }
                     }
diff --git a/Content.Client/GameObjects/Components/Disposal/DisposalUnitWindow.cs b/Content.Client/GameObjects/Components/Disposal/DisposalUnitWindow.cs
index ca2c97edc3..742506a69e 100644
--- a/Content.Client/GameObjects/Components/Disposal/DisposalUnitWindow.cs
+++ b/Content.Client/GameObjects/Components/Disposal/DisposalUnitWindow.cs
@@ -21,10 +21,10 @@ namespace Content.Client.GameObjects.Components.Disposal
         public readonly Button Eject;
         public readonly Button Power;
 
-        protected override Vector2? CustomSize => (300, 200);
-
         public DisposalUnitWindow()
         {
+            MinSize = SetSize = (300, 200);
+
             Contents.AddChild(new VBoxContainer
             {
                 Children =
@@ -37,7 +37,7 @@ namespace Content.Client.GameObjects.Components.Disposal
                             (_unitState = new Label {Text = Loc.GetString("Ready")})
                         }
                     },
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
@@ -45,8 +45,8 @@ namespace Content.Client.GameObjects.Components.Disposal
                             new Label {Text = Loc.GetString("Pressure:")},
                             (_pressureBar = new ProgressBar
                             {
-                                CustomMinimumSize = (200, 20),
-                                SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
+                                MinSize = (200, 20),
+                                HorizontalAlignment = HAlignment.Right,
                                 MinValue = 0,
                                 MaxValue = 1,
                                 Page = 0,
@@ -58,7 +58,7 @@ namespace Content.Client.GameObjects.Components.Disposal
                             })
                         }
                     },
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
@@ -71,7 +71,7 @@ namespace Content.Client.GameObjects.Components.Disposal
                             })
                         }
                     },
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
@@ -80,7 +80,7 @@ namespace Content.Client.GameObjects.Components.Disposal
                             (Eject = new Button {Text = Loc.GetString("Eject Contents")})
                         }
                     },
-                    new Control {CustomMinimumSize = (0, 10)},
+                    new Control {MinSize = (0, 10)},
                     new HBoxContainer
                     {
                         Children =
diff --git a/Content.Client/GameObjects/Components/Gravity/GravityGeneratorBoundUserInterface.cs b/Content.Client/GameObjects/Components/Gravity/GravityGeneratorBoundUserInterface.cs
index e921ae792d..0888d4eed3 100644
--- a/Content.Client/GameObjects/Components/Gravity/GravityGeneratorBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/Gravity/GravityGeneratorBoundUserInterface.cs
@@ -73,7 +73,7 @@ namespace Content.Client.GameObjects.Components.Gravity
 
             var vBox = new VBoxContainer
             {
-                CustomMinimumSize = new Vector2(250, 100)
+                MinSize = new Vector2(250, 100)
             };
             Status = new Label
             {
@@ -84,7 +84,7 @@ namespace Content.Client.GameObjects.Components.Gravity
             {
                 Text = Loc.GetString(Owner.IsOn ? "Turn Off" : "Turn On"),
                 TextAlign = Label.AlignMode.Center,
-                CustomMinimumSize = new Vector2(150, 60)
+                MinSize = new Vector2(150, 60)
             };
 
             vBox.AddChild(Status);
diff --git a/Content.Client/GameObjects/Components/HUD/Inventory/HumanInventoryInterfaceController.cs b/Content.Client/GameObjects/Components/HUD/Inventory/HumanInventoryInterfaceController.cs
index 991abd84ed..b224855a50 100644
--- a/Content.Client/GameObjects/Components/HUD/Inventory/HumanInventoryInterfaceController.cs
+++ b/Content.Client/GameObjects/Components/HUD/Inventory/HumanInventoryInterfaceController.cs
@@ -87,7 +87,7 @@ namespace Content.Client.GameObjects.Components.HUD.Inventory
                     _hudButtonPocket1,
                     _hudButtonPocket2,
                     // keeps this "balanced" with the left, so the hands will appear perfectly in the center
-                    new Control{CustomMinimumSize = (64, 64)}
+                    new Control{MinSize = (64, 64)}
                 },
                 SeparationOverride = 5
             };
@@ -226,7 +226,7 @@ namespace Content.Client.GameObjects.Components.HUD.Inventory
                 const int width = ButtonSize * 4 + ButtonSeparation * 3 + RightSeparation;
                 const int height = ButtonSize * 4 + ButtonSeparation * 3;
 
-                var windowContents = new LayoutContainer {CustomMinimumSize = (width, height)};
+                var windowContents = new LayoutContainer {MinSize = (width, height)};
                 Contents.AddChild(windowContents);
 
                 void AddButton(Slots slot, string textureName, Vector2 position)
diff --git a/Content.Client/GameObjects/Components/HandheldLightComponent.cs b/Content.Client/GameObjects/Components/HandheldLightComponent.cs
index 6566984e07..bc80ed66e2 100644
--- a/Content.Client/GameObjects/Components/HandheldLightComponent.cs
+++ b/Content.Client/GameObjects/Components/HandheldLightComponent.cs
@@ -57,14 +57,14 @@ namespace Content.Client.GameObjects.Components
                 var wrapper = new HBoxContainer
                 {
                     SeparationOverride = 4,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center
                 };
 
                 AddChild(wrapper);
 
                 for (var i = 0; i < _sections.Length; i++)
                 {
-                    var panel = new PanelContainer {CustomMinimumSize = (20, 20)};
+                    var panel = new PanelContainer {MinSize = (20, 20)};
                     wrapper.AddChild(panel);
                     _sections[i] = panel;
                 }
diff --git a/Content.Client/GameObjects/Components/Kitchen/MicrowaveBoundUserInterface.cs b/Content.Client/GameObjects/Components/Kitchen/MicrowaveBoundUserInterface.cs
index 6df5a5d77d..dfe1efb6a7 100644
--- a/Content.Client/GameObjects/Components/Kitchen/MicrowaveBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/Kitchen/MicrowaveBoundUserInterface.cs
@@ -139,8 +139,6 @@ namespace Content.Client.GameObjects.Components.Kitchen
             }
 
 
-            protected override Vector2? CustomSize => (512, 256);
-
             private MicrowaveBoundUserInterface Owner { get; set; }
 
             public event Action<BaseButton.ButtonEventArgs, int> OnCookTimeSelected;
@@ -165,54 +163,49 @@ namespace Content.Client.GameObjects.Components.Kitchen
 
             public MicrowaveMenu(MicrowaveBoundUserInterface owner = null)
             {
+                SetSize = MinSize = (512, 256);
+
                 Owner = owner;
                 Title = Loc.GetString("Microwave");
                 DisableCookingPanelOverlay = new PanelContainer
                 {
                     MouseFilter = MouseFilterMode.Stop,
                     PanelOverride = new StyleBoxFlat {BackgroundColor = Color.Black.WithAlpha(0.60f)},
-                    SizeFlagsHorizontal = SizeFlags.Fill,
-                    SizeFlagsVertical = SizeFlags.Fill,
                 };
 
-
-                var hSplit = new HBoxContainer
-                {
-                    SizeFlagsHorizontal = SizeFlags.Fill,
-                    SizeFlagsVertical = SizeFlags.Fill
-                };
+                var hSplit = new HBoxContainer();
 
                 IngredientsListReagents = new ItemList
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     SelectMode = ItemList.ItemListSelectMode.Button,
                     SizeFlagsStretchRatio = 2,
-                    CustomMinimumSize = (100, 128)
+                    MinSize = (100, 128)
                 };
 
                 IngredientsList = new ItemList
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     SelectMode = ItemList.ItemListSelectMode.Button,
                     SizeFlagsStretchRatio = 2,
-                    CustomMinimumSize = (100, 128)
+                    MinSize = (100, 128)
                 };
 
                 hSplit.AddChild(IngredientsListReagents);
                 //Padding between the lists.
                 hSplit.AddChild(new Control
                 {
-                    CustomMinimumSize = (0, 5),
+                    MinSize = (0, 5),
                 });
 
                 hSplit.AddChild(IngredientsList);
 
                 var vSplit = new VBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                 };
 
                 hSplit.AddChild(vSplit);
@@ -243,14 +236,13 @@ namespace Content.Client.GameObjects.Components.Kitchen
                 //Padding
                 vSplit.AddChild(new Control
                 {
-                    CustomMinimumSize = (0, 15),
-                    SizeFlagsVertical = SizeFlags.Fill,
+                    MinSize = (0, 15),
                 });
 
                 CookTimeButtonGroup = new ButtonGroup();
                 CookTimeButtonVbox = new VBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
                     Align = BoxContainer.AlignMode.Center,
                 };
 
@@ -284,14 +276,14 @@ namespace Content.Client.GameObjects.Components.Kitchen
                     Text = Loc.GetString("COOK TIME: 1"),
                     Align = Label.AlignMode.Center,
                     Modulate = Color.White,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    VerticalAlignment = VAlignment.Center
                 };
 
                 var innerTimerPanel = new PanelContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
                     ModulateSelfOverride = Color.Red,
-                    CustomMinimumSize = (100, 128),
+                    MinSize = (100, 128),
                     PanelOverride = new StyleBoxFlat {BackgroundColor = Color.Black.WithAlpha(0.5f)},
 
                     Children =
@@ -312,7 +304,7 @@ namespace Content.Client.GameObjects.Components.Kitchen
 
                                 new ScrollContainer()
                                 {
-                                    SizeFlagsVertical = SizeFlags.FillExpand,
+                                    VerticalExpand = true,
 
                                     Children =
                                     {
@@ -326,8 +318,8 @@ namespace Content.Client.GameObjects.Components.Kitchen
 
                 TimerFacePlate = new PanelContainer()
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     Children =
                     {
                         innerTimerPanel
diff --git a/Content.Client/GameObjects/Components/Kitchen/ReagentGrinderBoundUserInterface.cs b/Content.Client/GameObjects/Components/Kitchen/ReagentGrinderBoundUserInterface.cs
index f59bc077fc..f9c17cae51 100644
--- a/Content.Client/GameObjects/Components/Kitchen/ReagentGrinderBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/Kitchen/ReagentGrinderBoundUserInterface.cs
@@ -156,7 +156,6 @@ namespace Content.Client.GameObjects.Components.Kitchen
              */
 
             private ReagentGrinderBoundUserInterface Owner { get; set; }
-            protected override Vector2? CustomSize => (512, 256);
 
             //We'll need 4 buttons, grind, juice, eject beaker, eject the chamber contents.
             //The other 2 are referenced in the Open function.
@@ -202,11 +201,11 @@ namespace Content.Client.GameObjects.Components.Kitchen
                     AddChild(vSplit);
                     BoxContents = new ItemList
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        VerticalExpand = true,
+                        HorizontalExpand = true,
                         SelectMode = ItemList.ItemListSelectMode.Button,
                         SizeFlagsStretchRatio = 2,
-                        CustomMinimumSize = (100, 128)
+                        MinSize = (100, 128)
                     };
                     AddChild(BoxContents);
                 }
@@ -214,47 +213,44 @@ namespace Content.Client.GameObjects.Components.Kitchen
 
             public GrinderMenu(ReagentGrinderBoundUserInterface owner = null)
             {
+                SetSize = MinSize = (512, 256);
                 Owner = owner;
                 Title = Loc.GetString("All-In-One Grinder 3000");
 
-                var hSplit = new HBoxContainer
-                {
-                    SizeFlagsHorizontal = SizeFlags.Fill,
-                    SizeFlagsVertical = SizeFlags.Fill
-                };
+                var hSplit = new HBoxContainer();
 
                 var vBoxGrindJuiceButtonPanel = new VBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    VerticalAlignment = VAlignment.Center
                 };
 
                 GrindButton = new Button
                 {
                     Text = Loc.GetString("Grind"),
                     TextAlign = Label.AlignMode.Center,
-                    CustomMinimumSize = (64, 64)
+                    MinSize = (64, 64)
                 };
 
                 JuiceButton = new Button
                 {
                     Text = Loc.GetString("Juice"),
                     TextAlign = Label.AlignMode.Center,
-                    CustomMinimumSize = (64, 64)
+                    MinSize = (64, 64)
                 };
 
                 vBoxGrindJuiceButtonPanel.AddChild(GrindButton);
                 //inner button padding
                 vBoxGrindJuiceButtonPanel.AddChild(new Control
                 {
-                    CustomMinimumSize = (0, 16),
+                    MinSize = (0, 16),
                 });
                 vBoxGrindJuiceButtonPanel.AddChild(JuiceButton);
 
                 ChamberContentBox = new LabelledContentBox(Loc.GetString("Chamber"), Loc.GetString("Eject Contents"))
                 {
                     //Modulate = Color.Red,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     SizeFlagsStretchRatio = 2,
 
                 };
@@ -262,8 +258,8 @@ namespace Content.Client.GameObjects.Components.Kitchen
                 BeakerContentBox = new LabelledContentBox(Loc.GetString("Beaker"), Loc.GetString("Eject Beaker"))
                 {
                     //Modulate = Color.Blue,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     SizeFlagsStretchRatio = 2,
                 };
 
@@ -272,14 +268,14 @@ namespace Content.Client.GameObjects.Components.Kitchen
                 //Padding between the g/j buttons panel and the itemlist boxes panel.
                 hSplit.AddChild(new Control
                 {
-                    CustomMinimumSize = (16, 0),
+                    MinSize = (16, 0),
                 });
                 hSplit.AddChild(ChamberContentBox);
 
                 //Padding between the two itemlists.
                 hSplit.AddChild(new Control
                 {
-                    CustomMinimumSize = (8, 0),
+                    MinSize = (8, 0),
                 });
                 hSplit.AddChild(BeakerContentBox);
                 Contents.AddChild(hSplit);
diff --git a/Content.Client/GameObjects/Components/MagicMirrorBoundUserInterface.cs b/Content.Client/GameObjects/Components/MagicMirrorBoundUserInterface.cs
index 486845334b..3a8100af1f 100644
--- a/Content.Client/GameObjects/Components/MagicMirrorBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/MagicMirrorBoundUserInterface.cs
@@ -136,8 +136,8 @@ namespace Content.Client.GameObjects.Components
 
             Items = new ItemList
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                CustomMinimumSize = (300, 250)
+                VerticalExpand = true,
+                MinSize = (300, 250)
             };
             vBox.AddChild(Items);
             Items.OnItemSelected += ItemSelected;
@@ -202,13 +202,13 @@ namespace Content.Client.GameObjects.Components
                 _slider = new Slider
                 {
                     StyleClasses = {styleClass},
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalExpand = true,
+                    VerticalAlignment = VAlignment.Center,
                     MaxValue = byte.MaxValue
                 };
                 _textBox = new LineEdit
                 {
-                    CustomMinimumSize = (50, 0)
+                    MinSize = (50, 0)
                 };
 
                 AddChild(new HBoxContainer
@@ -261,18 +261,17 @@ namespace Content.Client.GameObjects.Components
         private readonly HairStylePicker _hairStylePicker;
         private readonly FacialHairStylePicker _facialHairStylePicker;
 
-        protected override Vector2? CustomSize => (500, 360);
-
         public MagicMirrorWindow(MagicMirrorBoundUserInterface owner)
         {
+            SetSize = MinSize = (500, 360);
             Title = Loc.GetString("Magic Mirror");
 
-            _hairStylePicker = new HairStylePicker {SizeFlagsHorizontal = SizeFlags.FillExpand};
+            _hairStylePicker = new HairStylePicker {HorizontalExpand = true};
             _hairStylePicker.Populate();
             _hairStylePicker.OnHairStylePicked += newStyle => owner.HairSelected(newStyle, false);
             _hairStylePicker.OnHairColorPicked += newColor => owner.HairColorSelected(newColor, false);
 
-            _facialHairStylePicker = new FacialHairStylePicker {SizeFlagsHorizontal = SizeFlags.FillExpand};
+            _facialHairStylePicker = new FacialHairStylePicker {HorizontalExpand = true};
             _facialHairStylePicker.Populate();
             _facialHairStylePicker.OnHairStylePicked += newStyle => owner.HairSelected(newStyle, true);
             _facialHairStylePicker.OnHairColorPicked += newColor => owner.HairColorSelected(newColor, true);
diff --git a/Content.Client/GameObjects/Components/MedicalScanner/MedicalScannerWindow.cs b/Content.Client/GameObjects/Components/MedicalScanner/MedicalScannerWindow.cs
index 853d00b43b..87ead148c1 100644
--- a/Content.Client/GameObjects/Components/MedicalScanner/MedicalScannerWindow.cs
+++ b/Content.Client/GameObjects/Components/MedicalScanner/MedicalScannerWindow.cs
@@ -14,10 +14,10 @@ namespace Content.Client.GameObjects.Components.MedicalScanner
     {
         public readonly Button ScanButton;
         private readonly Label _diagnostics;
-        protected override Vector2? CustomSize => (485, 90);
-
         public MedicalScannerWindow()
         {
+            MinSize = SetSize = (485, 90);
+
             Contents.AddChild(new VBoxContainer
             {
                 Children =
diff --git a/Content.Client/GameObjects/Components/Observer/AcceptCloningWindow.cs b/Content.Client/GameObjects/Components/Observer/AcceptCloningWindow.cs
index ef1f39b881..b7d3a69d27 100644
--- a/Content.Client/GameObjects/Components/Observer/AcceptCloningWindow.cs
+++ b/Content.Client/GameObjects/Components/Observer/AcceptCloningWindow.cs
@@ -40,7 +40,7 @@ namespace Content.Client.GameObjects.Components.Observer
 
                                     (new Control()
                                     {
-                                        CustomMinimumSize = (20, 0)
+                                        MinSize = (20, 0)
                                     }),
 
                                     (DenyButton = new Button
diff --git a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesEntry.xaml b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesEntry.xaml
index 83ad91c3f1..60ac1dc697 100644
--- a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesEntry.xaml
+++ b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesEntry.xaml
@@ -3,7 +3,7 @@
 
     <RichTextLabel Name="Title" />
     <HBoxContainer SeparationOverride="10">
-        <RichTextLabel Name="Description" SizeFlagsHorizontal="FillExpand" />
+        <RichTextLabel Name="Description" HorizontalExpand="True" />
         <Button Name="RequestButton" Text="Request" TextAlign="Center" SizeFlagsHorizontal="ShrinkEnd" />
     </HBoxContainer>
 </VBoxContainer>
diff --git a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml
index 221f26aa5c..8f6de8f9c3 100644
--- a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml
+++ b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml
@@ -1,10 +1,10 @@
 <SS14Window Title="Ghost Roles"
-            xmlns="https://spacestation14.io">
-    <CenterContainer Name="NoRolesMessage" SizeFlagsVertical="FillExpand" SizeFlagsHorizontal="FillExpand">
+            xmlns="https://spacestation14.io" MinSize="350 275">
+    <CenterContainer Name="NoRolesMessage" VerticalExpand="True" HorizontalExpand="True">
         <Label Text="There are currently no available ghost roles." />
     </CenterContainer>
-    <ScrollContainer SizeFlagsHorizontal="FillExpand" SizeFlagsVertical="FillExpand">
-        <VBoxContainer Name="EntryContainer" SizeFlagsHorizontal="FillExpand" SizeFlagsVertical="FillExpand" />
+    <ScrollContainer HorizontalExpand="True" VerticalExpand="True">
+        <VBoxContainer Name="EntryContainer" HorizontalExpand="True" VerticalExpand="True" />
     </ScrollContainer>
 
 </SS14Window>
diff --git a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml.cs b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml.cs
index 59cead269c..3265f7c461 100644
--- a/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml.cs
+++ b/Content.Client/GameObjects/Components/Observer/GhostRoles/GhostRolesWindow.xaml.cs
@@ -12,8 +12,6 @@ namespace Content.Client.GameObjects.Components.Observer.GhostRoles
     {
         public event Action<uint> RoleRequested;
 
-        protected override Vector2 CalculateMinimumSize() => (350, 275);
-
         public void ClearEntries()
         {
             EntryContainer.DisposeAllChildren();
diff --git a/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml b/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml
index 4c775816a4..0a5dfa1850 100644
--- a/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml
+++ b/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml
@@ -8,11 +8,11 @@
         </HBoxContainer>
         <HBoxContainer>
             <Label Name="RoleNameLabel" Text="Role Name" />
-            <LineEdit Name="RoleName" SizeFlagsHorizontal="FillExpand" />
+            <LineEdit Name="RoleName" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
             <Label Name="RoleDescriptionLabel" Text="Role Description" />
-            <LineEdit Name="RoleDescription" SizeFlagsHorizontal="FillExpand" />
+            <LineEdit Name="RoleDescription" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
             <Label Name="MakeSentientLabel" Text="Make Sentient" />
diff --git a/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml.cs b/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml.cs
index c12400eee7..1140b7cb66 100644
--- a/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml.cs
+++ b/Content.Client/GameObjects/Components/Observer/GhostRoles/MakeGhostRoleWindow.xaml.cs
@@ -16,12 +16,12 @@ namespace Content.Client.GameObjects.Components.Observer.GhostRoles
         {
             RobustXamlLoader.Load(this);
 
-            MakeSentientLabel.CustomMinimumSize = (150, 0);
-            RoleEntityLabel.CustomMinimumSize = (150, 0);
-            RoleNameLabel.CustomMinimumSize = (150, 0);
-            RoleName.CustomMinimumSize = (300, 0);
-            RoleDescriptionLabel.CustomMinimumSize = (150, 0);
-            RoleDescription.CustomMinimumSize = (300, 0);
+            MakeSentientLabel.MinSize = (150, 0);
+            RoleEntityLabel.MinSize = (150, 0);
+            RoleNameLabel.MinSize = (150, 0);
+            RoleName.MinSize = (300, 0);
+            RoleDescriptionLabel.MinSize = (150, 0);
+            RoleDescription.MinSize = (300, 0);
 
             MakeButton.OnPressed += OnPressed;
         }
diff --git a/Content.Client/GameObjects/Components/PDA/PDABoundUserInterface.cs b/Content.Client/GameObjects/Components/PDA/PDABoundUserInterface.cs
index 6f3ad685b6..8ea973f6c0 100644
--- a/Content.Client/GameObjects/Components/PDA/PDABoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/PDA/PDABoundUserInterface.cs
@@ -221,8 +221,6 @@ namespace Content.Client.GameObjects.Components.PDA
 
         private class PDAMenu : SS14Window
         {
-            protected override Vector2? CustomSize => (512, 256);
-
             private PDABoundUserInterface _owner { get; }
 
             public Button FlashLightToggleButton { get; }
@@ -275,6 +273,8 @@ namespace Content.Client.GameObjects.Components.PDA
 
             public PDAMenu(PDABoundUserInterface owner, IPrototypeManager prototypeManager)
             {
+                MinSize = SetSize = (512, 256);
+
                 _owner = owner;
                 _prototypeManager = prototypeManager;
                 Title = Loc.GetString("PDA");
@@ -287,20 +287,20 @@ namespace Content.Client.GameObjects.Components.PDA
 
                 IDInfoLabel = new RichTextLabel()
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                 };
 
                 EjectIDButton = new Button
                 {
                     Text = Loc.GetString("Eject ID"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center,
+                    VerticalAlignment = VAlignment.Center
                 };
                 EjectPenButton = new Button
                 {
                     Text = Loc.GetString("Eject Pen"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center,
+                    VerticalAlignment = VAlignment.Center
                 };
 
                 var innerHBoxContainer = new HBoxContainer
@@ -315,7 +315,6 @@ namespace Content.Client.GameObjects.Components.PDA
 
                 IDInfoContainer = new PanelContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.Fill,
                     Children =
                     {
                         innerHBoxContainer,
@@ -330,9 +329,9 @@ namespace Content.Client.GameObjects.Components.PDA
 
                 var mainMenuTabContainer = new VBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    CustomMinimumSize = (50, 50),
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
+                    MinSize = (50, 50),
 
                     Children =
                     {
@@ -352,36 +351,36 @@ namespace Content.Client.GameObjects.Components.PDA
 
                 BalanceInfo = new RichTextLabel
                 {
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
+                    HorizontalAlignment = HAlignment.Center,
                 };
 
                 //Red background container.
                 var masterPanelContainer = new PanelContainer
                 {
                     PanelOverride = new StyleBoxFlat { BackgroundColor = Color.Black },
-                    SizeFlagsVertical = SizeFlags.FillExpand
+                    VerticalExpand = true
                 };
 
                 //This contains both the panel of the category buttons and the listings box.
                 CategoryAndListingsContainer = new HSplitContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
                 };
 
 
                 var uplinkShopScrollContainer = new ScrollContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
+                    VerticalExpand = true,
                     SizeFlagsStretchRatio = 2,
-                    CustomMinimumSize = (100, 256)
+                    MinSize = (100, 256)
                 };
 
                 //Add the category list to the left side. The store items to center.
                 var categoryListContainerBackground = new PanelContainer
                 {
                     PanelOverride = new StyleBoxFlat { BackgroundColor = Color.Gray.WithAlpha(0.02f) },
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
                     Children =
                     {
                         CategoryListContainer
@@ -395,16 +394,16 @@ namespace Content.Client.GameObjects.Components.PDA
                 //Actual list of buttons for buying a listing from the uplink.
                 UplinkListingsContainer = new VBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
+                    VerticalExpand = true,
                     SizeFlagsStretchRatio = 2,
-                    CustomMinimumSize = (100, 256),
+                    MinSize = (100, 256),
                 };
                 uplinkShopScrollContainer.AddChild(UplinkListingsContainer);
 
                 var innerVboxContainer = new VBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
 
                     Children =
                     {
@@ -472,7 +471,7 @@ namespace Content.Client.GameObjects.Components.PDA
                 {
                     Text = listing.ListingName == string.Empty ? prototype.Name : listing.ListingName,
                     ToolTip = listing.Description == string.Empty ? prototype.Description : listing.Description,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     Modulate = _loggedInUplinkAccount.DataBalance >= listing.Price
                     ? Color.White
                     : Color.Gray.WithAlpha(0.30f)
@@ -481,7 +480,7 @@ namespace Content.Client.GameObjects.Components.PDA
                 var priceLabel = new Label
                 {
                     Text = $"{listing.Price} TC",
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
+                    HorizontalAlignment = HAlignment.Right,
                     Modulate = _loggedInUplinkAccount.DataBalance >= listing.Price
                     ? weightedColor
                     : Color.Gray.WithAlpha(0.30f)
@@ -490,8 +489,7 @@ namespace Content.Client.GameObjects.Components.PDA
                 //Padding for the price lable.
                 var pricePadding = new HBoxContainer
                 {
-                    CustomMinimumSize = (32, 1),
-                    SizeFlagsHorizontal = SizeFlags.Fill,
+                    MinSize = (32, 1),
                 };
 
                 //Contains the name of the item and its price. Used for spacing item name and price.
@@ -516,7 +514,6 @@ namespace Content.Client.GameObjects.Components.PDA
                 var pdaUplinkListingButton = new PDAUplinkItemButton
                 {
                     ButtonListing = listing,
-                    SizeFlagsVertical = SizeFlags.Fill,
                     Children =
                     {
                         listingButtonPanelContainer
diff --git a/Content.Client/GameObjects/Components/Paper/PaperWindow.cs b/Content.Client/GameObjects/Components/Paper/PaperWindow.cs
index f34bdf1bd2..f4e3905e4f 100644
--- a/Content.Client/GameObjects/Components/Paper/PaperWindow.cs
+++ b/Content.Client/GameObjects/Components/Paper/PaperWindow.cs
@@ -10,10 +10,10 @@ namespace Content.Client.GameObjects.Components.Paper
     {
         private readonly RichTextLabel _label;
         public readonly LineEdit Input;
-        protected override Vector2? CustomSize => (300, 300);
 
         public PaperWindow()
         {
+            MinSize = SetSize = (300, 300);
             var container = new VBoxContainer();
             _label = new RichTextLabel();
             Input = new LineEdit {Visible = false};
diff --git a/Content.Client/GameObjects/Components/Power/ApcBoundUserInterface.cs b/Content.Client/GameObjects/Components/Power/ApcBoundUserInterface.cs
index 9a4fe31049..6a7a77408f 100644
--- a/Content.Client/GameObjects/Components/Power/ApcBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/Power/ApcBoundUserInterface.cs
@@ -151,7 +151,7 @@ namespace Content.Client.GameObjects.Components.Power
                 var chargeLabel = new Label {Text = "Charge:"};
                 ChargeBar = new ProgressBar
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     MinValue = 0.0f,
                     MaxValue = 1.0f,
                     Page = 0.0f,
diff --git a/Content.Client/GameObjects/Components/Power/SolarControlConsoleBoundUserInterface.cs b/Content.Client/GameObjects/Components/Power/SolarControlConsoleBoundUserInterface.cs
index 0a005e6598..efef0ea092 100644
--- a/Content.Client/GameObjects/Components/Power/SolarControlConsoleBoundUserInterface.cs
+++ b/Content.Client/GameObjects/Components/Power/SolarControlConsoleBoundUserInterface.cs
@@ -139,18 +139,14 @@ namespace Content.Client.GameObjects.Components.Power
                 rows.AddChild(new Label {Text = "Press Enter to confirm."});
                 rows.AddChild(new Label {Text = ""});
 
-                PanelRotation.SizeFlagsHorizontal = SizeFlags.FillExpand;
-                PanelVelocity.SizeFlagsHorizontal = SizeFlags.FillExpand;
-                rows.SizeFlagsHorizontal = SizeFlags.Fill;
-                rows.SizeFlagsVertical = SizeFlags.Fill;
+                PanelRotation.HorizontalExpand = true;
+                PanelVelocity.HorizontalExpand = true;
 
                 NotARadar = new SolarControlNotARadar(igt);
 
                 var outerColumns = new HBoxContainer();
                 outerColumns.AddChild(rows);
                 outerColumns.AddChild(NotARadar);
-                outerColumns.SizeFlagsHorizontal = SizeFlags.Fill;
-                outerColumns.SizeFlagsVertical = SizeFlags.Fill;
                 Contents.AddChild(outerColumns);
                 Resizable = false;
             }
@@ -173,6 +169,7 @@ namespace Content.Client.GameObjects.Components.Power
             public SolarControlNotARadar(IGameTiming igt)
             {
                 _gameTiming = igt;
+                MinSize = (SizeFull, SizeFull);
             }
 
             public void UpdateState(SolarControlConsoleBoundInterfaceState ls)
@@ -181,11 +178,6 @@ namespace Content.Client.GameObjects.Components.Power
                 _lastStateTime = _gameTiming.CurTime;
             }
 
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return (SizeFull, SizeFull);
-            }
-
             protected override void Draw(DrawingHandleScreen handle)
             {
                 int point = SizeFull / 2;
diff --git a/Content.Client/GameObjects/Components/Research/ResearchClientServerSelectionMenu.cs b/Content.Client/GameObjects/Components/Research/ResearchClientServerSelectionMenu.cs
index 4b76477d58..39957f0e03 100644
--- a/Content.Client/GameObjects/Components/Research/ResearchClientServerSelectionMenu.cs
+++ b/Content.Client/GameObjects/Components/Research/ResearchClientServerSelectionMenu.cs
@@ -14,11 +14,11 @@ namespace Content.Client.GameObjects.Components.Research
         private int[] _serverIds = new int[]{};
         private int _selectedServerId = -1;
 
-        protected override Vector2? CustomSize => (300, 300);
         public ResearchClientBoundUserInterface Owner { get; set; }
 
         public ResearchClientServerSelectionMenu()
         {
+            MinSize = SetSize = (300, 300);
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("Research Server Selection");
@@ -28,19 +28,7 @@ namespace Content.Client.GameObjects.Components.Research
             _servers.OnItemSelected += OnItemSelected;
             _servers.OnItemDeselected += OnItemDeselected;
 
-            var margin = new MarginContainer()
-            {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                /*MarginTop = 5f,
-                MarginLeft = 5f,
-                MarginRight = -5f,
-                MarginBottom = -5f,*/
-            };
-
-            margin.AddChild(_servers);
-
-            Contents.AddChild(margin);
+            Contents.AddChild(_servers);
         }
 
         public void OnItemSelected(ItemList.ItemListSelectedEventArgs itemListSelectedEventArgs)
diff --git a/Content.Client/GameObjects/Components/Storage/ClientStorageComponent.cs b/Content.Client/GameObjects/Components/Storage/ClientStorageComponent.cs
index fb5f9117fc..5088e1a4b9 100644
--- a/Content.Client/GameObjects/Components/Storage/ClientStorageComponent.cs
+++ b/Content.Client/GameObjects/Components/Storage/ClientStorageComponent.cs
@@ -37,7 +37,7 @@ namespace Content.Client.GameObjects.Components.Storage
         public override void Initialize()
         {
             base.Initialize();
-            
+
             // Hide stackVisualizer on start
             _bagState = SharedBagState.Close;
         }
@@ -132,7 +132,7 @@ namespace Content.Client.GameObjects.Components.Storage
         private void ToggleUI()
         {
             if (Window.IsOpen)
-                
+
                 Window.Close();
             else
                 Window.Open();
@@ -142,7 +142,7 @@ namespace Content.Client.GameObjects.Components.Storage
         {
             Window.Close();
         }
-        
+
         private void ChangeStorageVisualization(SharedBagState state)
         {
             _bagState = state;
@@ -186,25 +186,20 @@ namespace Content.Client.GameObjects.Components.Storage
             private readonly StyleBoxFlat _hoveredBox = new() { BackgroundColor = Color.Black.WithAlpha(0.35f) };
             private readonly StyleBoxFlat _unHoveredBox = new() { BackgroundColor = Color.Black.WithAlpha(0.0f) };
 
-            protected override Vector2? CustomSize => (180, 320);
-
             public StorageWindow()
             {
+                MinSize = SetSize = (180, 320);
                 Title = "Storage Item";
                 RectClipContent = true;
 
                 var containerButton = new ContainerButton
                 {
-                    SizeFlagsHorizontal = SizeFlags.Fill,
-                    SizeFlagsVertical = SizeFlags.Fill,
                     MouseFilter = MouseFilterMode.Pass,
                 };
 
                 var innerContainerButton = new PanelContainer
                 {
                     PanelOverride = _unHoveredBox,
-                    SizeFlagsHorizontal = SizeFlags.Fill,
-                    SizeFlagsVertical = SizeFlags.Fill,
                 };
 
 
@@ -227,20 +222,20 @@ namespace Content.Client.GameObjects.Components.Storage
                 _information = new Label
                 {
                     Text = "Items: 0 Volume: 0/0 Stuff",
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    VerticalAlignment = VAlignment.Center
                 };
                 VSplitContainer.AddChild(_information);
 
                 var listScrollContainer = new ScrollContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    VerticalExpand = true,
+                    HorizontalExpand = true,
                     HScrollEnabled = true,
                     VScrollEnabled = true,
                 };
                 _entityList = new VBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                    HorizontalExpand = true
                 };
                 listScrollContainer.AddChild(_entityList);
                 VSplitContainer.AddChild(listScrollContainer);
@@ -342,8 +337,8 @@ namespace Content.Client.GameObjects.Components.Storage
             {
                 ActualButton = new Button
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
+                    VerticalExpand = true,
                     ToggleMode = true,
                     MouseFilter = MouseFilterMode.Stop
                 };
@@ -352,11 +347,11 @@ namespace Content.Client.GameObjects.Components.Storage
                 var hBoxContainer = new HBoxContainer();
                 EntitySpriteView = new SpriteView
                 {
-                    CustomMinimumSize = new Vector2(32.0f, 32.0f)
+                    MinSize = new Vector2(32.0f, 32.0f)
                 };
                 EntityName = new Label
                 {
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    VerticalAlignment = VAlignment.Center,
                     Text = "Backpack",
                 };
                 hBoxContainer.AddChild(EntitySpriteView);
@@ -364,11 +359,11 @@ namespace Content.Client.GameObjects.Components.Storage
 
                 EntityControl = new Control
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                    HorizontalExpand = true
                 };
                 EntitySize = new Label
                 {
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    VerticalAlignment = VAlignment.Center,
                     Text = "Size 6",
                     Align = Label.AlignMode.Right,
                     /*AnchorLeft = 1.0f,
diff --git a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBatteryBarrelComponent.cs b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBatteryBarrelComponent.cs
index dd1c77c895..6c0e84f812 100644
--- a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBatteryBarrelComponent.cs
+++ b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBatteryBarrelComponent.cs
@@ -63,23 +63,24 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
             public StatusControl(ClientBatteryBarrelComponent parent)
             {
+                MinHeight = 15;
                 _parent = parent;
-                SizeFlagsHorizontal = SizeFlags.FillExpand;
-                SizeFlagsVertical = SizeFlags.ShrinkCenter;
+                HorizontalExpand = true;
+                VerticalAlignment = VAlignment.Center;
 
                 AddChild(new HBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     Children =
                     {
                         new Control
                         {
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             Children =
                             {
                                 (_bulletsList = new HBoxContainer
                                 {
-                                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                                    VerticalAlignment = VAlignment.Center,
                                     SeparationOverride = 4
                                 }),
                                 (_noBatteryLabel = new Label
@@ -89,11 +90,11 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                                 })
                             }
                         },
-                        new Control() { CustomMinimumSize = (5,0) },
+                        new Control() { MinSize = (5,0) },
                         (_ammoCount = new Label
                         {
                             StyleClasses = {StyleNano.StyleClassItemStatus},
-                            SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
+                            HorizontalAlignment = HAlignment.Right,
                         }),
                     }
                 });
@@ -134,7 +135,7 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                         {
                             BackgroundColor = colorGone,
                         },
-                        CustomMinimumSize = (10, 15),
+                        MinSize = (10, 15),
                     });
                 }
 
@@ -148,15 +149,10 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                         {
                             BackgroundColor = color,
                         },
-                        CustomMinimumSize = (10, 15),
+                        MinSize = (10, 15),
                     });
                 }
             }
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return Vector2.ComponentMax((0, 15), base.CalculateMinimumSize());
-            }
         }
     }
 }
diff --git a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBoltActionBarrelComponent.cs b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBoltActionBarrelComponent.cs
index 087a12a944..7fcc980ad1 100644
--- a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBoltActionBarrelComponent.cs
+++ b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientBoltActionBarrelComponent.cs
@@ -73,30 +73,31 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
             public StatusControl(ClientBoltActionBarrelComponent parent)
             {
+                MinHeight = 15;
                 _parent = parent;
-                SizeFlagsHorizontal = SizeFlags.FillExpand;
-                SizeFlagsVertical = SizeFlags.ShrinkCenter;
+                HorizontalExpand = true;
+                VerticalAlignment = VAlignment.Center;
                 AddChild(new VBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalExpand = true,
+                    VerticalAlignment = VAlignment.Center,
                     SeparationOverride = 0,
                     Children =
                     {
                         (_bulletsListTop = new HBoxContainer {SeparationOverride = 0}),
                         new HBoxContainer
                         {
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             Children =
                             {
                                 new Control
                                 {
-                                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                    HorizontalExpand = true,
                                     Children =
                                     {
                                         (_bulletsListBottom = new HBoxContainer
                                         {
-                                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                                            VerticalAlignment = VAlignment.Center,
                                             SeparationOverride = 0
                                         }),
                                         (_noMagazineLabel = new Label
@@ -109,8 +110,8 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                                 (_chamberedBullet = new TextureRect
                                 {
                                     Texture = StaticIoC.ResC.GetTexture("/Textures/Interface/ItemStatus/Bullets/chambered.png"),
-                                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Fill,
+                                    VerticalAlignment = VAlignment.Center,
+                                    HorizontalAlignment = HAlignment.Right,
                                 })
                             }
                         }
@@ -198,11 +199,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     altColor ^= true;
                 }
             }
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return Vector2.ComponentMax((0, 15), base.CalculateMinimumSize());
-            }
         }
     }
 }
diff --git a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientMagazineBarrelComponent.cs b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientMagazineBarrelComponent.cs
index 019b63fca0..8304017321 100644
--- a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientMagazineBarrelComponent.cs
+++ b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientMagazineBarrelComponent.cs
@@ -146,30 +146,31 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
             public StatusControl(ClientMagazineBarrelComponent parent)
             {
+                MinHeight = 15;
                 _parent = parent;
-                SizeFlagsHorizontal = SizeFlags.FillExpand;
-                SizeFlagsVertical = SizeFlags.ShrinkCenter;
+                HorizontalExpand = true;
+                VerticalAlignment = VAlignment.Center;
 
                 AddChild(new HBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     Children =
                     {
                         (_chamberedBullet = new TextureRect
                         {
                             Texture = StaticIoC.ResC.GetTexture("/Textures/Interface/ItemStatus/Bullets/chambered_rotated.png"),
-                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                            SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Fill,
+                            VerticalAlignment = VAlignment.Center,
+                            HorizontalAlignment = HAlignment.Right,
                         }),
-                        new Control() { CustomMinimumSize = (5,0) },
+                        new Control() { MinSize = (5,0) },
                         new Control
                         {
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             Children =
                             {
                                 (_bulletsList = new HBoxContainer
                                 {
-                                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                                    VerticalAlignment = VAlignment.Center,
                                     SeparationOverride = 0
                                 }),
                                 (_noMagazineLabel = new Label
@@ -179,11 +180,11 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                                 })
                             }
                         },
-                        new Control() { CustomMinimumSize = (5,0) },
+                        new Control() { MinSize = (5,0) },
                         (_ammoCount = new Label
                         {
                             StyleClasses = {StyleNano.StyleClassItemStatus},
-                            SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
+                            HorizontalAlignment = HAlignment.Right,
                         }),
                     }
                 });
@@ -232,8 +233,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     {
                         Texture = texture,
                         ModulateSelfOverride = altColor ? colorGoneA : colorGoneB,
-                        SizeFlagsHorizontal = SizeFlags.Fill,
-                        SizeFlagsVertical = SizeFlags.Fill,
                         Stretch = TextureRect.StretchMode.KeepCentered
                     });
 
@@ -248,8 +247,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     {
                         Texture = texture,
                         ModulateSelfOverride = altColor ? colorA : colorB,
-                        SizeFlagsHorizontal = SizeFlags.Fill,
-                        SizeFlagsVertical = SizeFlags.Fill,
                         Stretch = TextureRect.StretchMode.KeepCentered
                     });
 
@@ -257,11 +254,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                 }
             }
 
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return Vector2.ComponentMax((0, 15), base.CalculateMinimumSize());
-            }
-
             public void PlayAlarmAnimation()
             {
                 var animation = _parent._isLmgAlarmAnimation ? AlarmAnimationLmg : AlarmAnimationSmg;
diff --git a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientPumpBarrelComponent.cs b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientPumpBarrelComponent.cs
index 2a7b286fcd..9e7b26e623 100644
--- a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientPumpBarrelComponent.cs
+++ b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientPumpBarrelComponent.cs
@@ -73,30 +73,31 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
             public StatusControl(ClientPumpBarrelComponent parent)
             {
+                MinHeight = 15;
                 _parent = parent;
-                SizeFlagsHorizontal = SizeFlags.FillExpand;
-                SizeFlagsVertical = SizeFlags.ShrinkCenter;
+                HorizontalExpand = true;
+                VerticalAlignment = VAlignment.Center;
                 AddChild(new VBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalExpand = true,
+                    VerticalAlignment = VAlignment.Center,
                     SeparationOverride = 0,
                     Children =
                     {
                         (_bulletsListTop = new HBoxContainer {SeparationOverride = 0}),
                         new HBoxContainer
                         {
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             Children =
                             {
                                 new Control
                                 {
-                                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                    HorizontalExpand = true,
                                     Children =
                                     {
                                         (_bulletsListBottom = new HBoxContainer
                                         {
-                                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                                            VerticalAlignment = VAlignment.Center,
                                             SeparationOverride = 0
                                         }),
                                         (_noMagazineLabel = new Label
@@ -109,8 +110,8 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                                 (_chamberedBullet = new TextureRect
                                 {
                                     Texture = StaticIoC.ResC.GetTexture("/Textures/Interface/ItemStatus/Bullets/chambered.png"),
-                                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Fill,
+                                    VerticalAlignment = VAlignment.Center,
+                                    HorizontalAlignment = HAlignment.Right,
                                 })
                             }
                         }
@@ -198,11 +199,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     altColor ^= true;
                 }
             }
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return Vector2.ComponentMax((0, 15), base.CalculateMinimumSize());
-            }
         }
     }
 }
diff --git a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientRevolverBarrelComponent.cs b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientRevolverBarrelComponent.cs
index 624ee64d25..1780006be3 100644
--- a/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientRevolverBarrelComponent.cs
+++ b/Content.Client/GameObjects/Components/Weapons/Ranged/Barrels/ClientRevolverBarrelComponent.cs
@@ -64,13 +64,14 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
             public StatusControl(ClientRevolverBarrelComponent parent)
             {
+                MinHeight = 15;
                 _parent = parent;
-                SizeFlagsHorizontal = SizeFlags.FillExpand;
-                SizeFlagsVertical = SizeFlags.ShrinkCenter;
+                HorizontalExpand = true;
+                VerticalAlignment = VAlignment.Center;
                 AddChild((_bulletsList = new HBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalExpand = true,
+                    VerticalAlignment = VAlignment.Center,
                     SeparationOverride = 0
                 }));
             }
@@ -119,7 +120,7 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     // Add a outline
                     var box = new Control()
                     {
-                        CustomMinimumSize = texture.Size * scale,
+                        MinSize = texture.Size * scale,
                     };
                     if (i == _parent.CurrentSlot)
                     {
@@ -152,8 +153,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
 
                     box.AddChild(new TextureRect
                     {
-                        SizeFlagsHorizontal = SizeFlags.Fill,
-                        SizeFlagsVertical = SizeFlags.Fill,
                         Stretch = TextureRect.StretchMode.KeepCentered,
                         Texture = bulletTexture,
                         ModulateSelfOverride = color,
@@ -162,11 +161,6 @@ namespace Content.Client.GameObjects.Components.Weapons.Ranged.Barrels
                     container.AddChild(box);
                 }
             }
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return Vector2.ComponentMax((0, 15), base.CalculateMinimumSize());
-            }
         }
     }
 }
diff --git a/Content.Client/GameObjects/Components/Wires/WiresMenu.cs b/Content.Client/GameObjects/Components/Wires/WiresMenu.cs
index 076de4173f..7a3773bfc4 100644
--- a/Content.Client/GameObjects/Components/Wires/WiresMenu.cs
+++ b/Content.Client/GameObjects/Components/Wires/WiresMenu.cs
@@ -72,30 +72,30 @@ namespace Content.Client.GameObjects.Components.Wires
                 {
                     new PanelContainer
                     {
-                        CustomMinimumSize = (2, 0),
+                        MinSize = (2, 0),
                         PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
                     },
                     new PanelContainer
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        HorizontalExpand = true,
                         MouseFilter = MouseFilterMode.Stop,
                         Name = "Shadow",
                         PanelOverride = new StyleBoxFlat {BackgroundColor = Color.Black.WithAlpha(0.5f)}
                     },
                     new PanelContainer
                     {
-                        CustomMinimumSize = (2, 0),
+                        MinSize = (2, 0),
                         PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
                     },
                 }
             };
 
             var wrappingHBox = new HBoxContainer();
-            _wiresHBox = new HBoxContainer {SeparationOverride = 4, SizeFlagsVertical = SizeFlags.ShrinkEnd};
+            _wiresHBox = new HBoxContainer {SeparationOverride = 4, VerticalAlignment = VAlignment.Bottom};
 
-            wrappingHBox.AddChild(new Control {CustomMinimumSize = (20, 0)});
+            wrappingHBox.AddChild(new Control {MinSize = (20, 0)});
             wrappingHBox.AddChild(_wiresHBox);
-            wrappingHBox.AddChild(new Control {CustomMinimumSize = (20, 0)});
+            wrappingHBox.AddChild(new Control {MinSize = (20, 0)});
 
             bottomWrap.AddChild(bottomPanel);
 
@@ -128,7 +128,7 @@ namespace Content.Client.GameObjects.Components.Wires
                 Children =
                 {
                     (_topContainer = new VBoxContainer()),
-                    new Control {CustomMinimumSize = (0, 110)}
+                    new Control {MinSize = (0, 110)}
                 }
             };
 
@@ -140,53 +140,38 @@ namespace Content.Client.GameObjects.Components.Wires
             var fontSmall = _resourceCache.GetFont("/Fonts/Boxfont-round/Boxfont Round.ttf", 10);
 
             Button helpButton;
-            var topRow = new MarginContainer
+            var topRow = new HBoxContainer
             {
-                MarginLeftOverride = 4,
-                MarginTopOverride = 2,
-                MarginRightOverride = 12,
-                MarginBottomOverride = 2,
+                Margin = new Thickness(4, 2, 12, 2),
                 Children =
                 {
-                    new HBoxContainer
+                    (_nameLabel = new Label
                     {
-                        Children =
-                        {
-                            (_nameLabel = new Label
-                            {
-                                Text = Loc.GetString("Wires"),
-                                FontOverride = font,
-                                FontColorOverride = StyleNano.NanoGold,
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            }),
-                            new Control
-                            {
-                                CustomMinimumSize = (8, 0),
-                            },
-                            (_serialLabel = new Label
-                            {
-                                Text = Loc.GetString("DEAD-BEEF"),
-                                FontOverride = fontSmall,
-                                FontColorOverride = Color.Gray,
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            }),
-                            new Control
-                            {
-                                CustomMinimumSize = (20, 0),
-                                SizeFlagsHorizontal = SizeFlags.Expand
-                            },
-                            (helpButton = new Button {Text = "?"}),
-                            new Control
-                            {
-                                CustomMinimumSize = (2, 0),
-                            },
-                            (CloseButton = new TextureButton
-                            {
-                                StyleClasses = {SS14Window.StyleClassWindowCloseButton},
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            })
-                        }
-                    }
+                        Text = Loc.GetString("Wires"),
+                        FontOverride = font,
+                        FontColorOverride = StyleNano.NanoGold,
+                        VerticalAlignment = VAlignment.Center,
+                    }),
+                    (_serialLabel = new Label
+                    {
+                        Text = Loc.GetString("DEAD-BEEF"),
+                        FontOverride = fontSmall,
+                        FontColorOverride = Color.Gray,
+                        VerticalAlignment = VAlignment.Center,
+                        Margin = new Thickness(8, 0, 20, 0),
+                        HorizontalAlignment = HAlignment.Left,
+                        HorizontalExpand = true,
+                    }),
+                    (helpButton = new Button
+                    {
+                        Text = "?",
+                        Margin = new Thickness(0, 0, 2, 0),
+                    }),
+                    (CloseButton = new TextureButton
+                    {
+                        StyleClasses = {SS14Window.StyleClassWindowCloseButton},
+                        VerticalAlignment = VAlignment.Center
+                    })
                 }
             };
 
@@ -207,21 +192,12 @@ namespace Content.Client.GameObjects.Components.Wires
                     {
                         Children =
                         {
-                            new MarginContainer
+                            (_statusContainer = new GridContainer
                             {
-                                MarginLeftOverride = 8,
-                                MarginRightOverride = 8,
-                                MarginTopOverride = 4,
-                                MarginBottomOverride = 4,
-                                Children =
-                                {
-                                    (_statusContainer = new GridContainer
-                                    {
-                                        // TODO: automatically change columns count.
-                                        Columns = 3
-                                    })
-                                }
-                            }
+                                Margin = new Thickness(8, 4),
+                                // TODO: automatically change columns count.
+                                Columns = 3
+                            })
                         }
                     }
                 }
@@ -230,17 +206,17 @@ namespace Content.Client.GameObjects.Components.Wires
             _topContainer.AddChild(topRow);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
+                MinSize = (0, 2),
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
             _topContainer.AddChild(middle);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
+                MinSize = (0, 2),
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
             CloseButton.OnPressed += _ => Close();
-            LayoutContainer.SetSize(this, (300, 200));
+            SetSize = (320, 200);
         }
 
 
@@ -258,7 +234,7 @@ namespace Content.Client.GameObjects.Components.Wires
                 var type = random.Next(2);
                 var control = new WireControl(wire.Color, wire.Letter, wire.IsCut, flip, mirror, type, _resourceCache)
                 {
-                    SizeFlagsVertical = SizeFlags.ShrinkEnd
+                    VerticalAlignment = VAlignment.Bottom
                 };
                 _wiresHBox.AddChild(control);
 
@@ -313,11 +289,12 @@ namespace Content.Client.GameObjects.Components.Wires
             public event Action WireClicked;
             public event Action ContactsClicked;
 
-            public WireControl(WireColor color, WireLetter letter, bool isCut, bool flip, bool mirror, int type, IResourceCache resourceCache)
+            public WireControl(WireColor color, WireLetter letter, bool isCut, bool flip, bool mirror, int type,
+                IResourceCache resourceCache)
             {
                 _resourceCache = resourceCache;
 
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter;
+                HorizontalAlignment = HAlignment.Center;
                 MouseFilter = MouseFilterMode.Stop;
 
                 var layout = new LayoutContainer();
@@ -326,8 +303,8 @@ namespace Content.Client.GameObjects.Components.Wires
                 var greek = new Label
                 {
                     Text = letter.Letter().ToString(),
-                    SizeFlagsVertical = SizeFlags.ShrinkEnd,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
+                    VerticalAlignment = VAlignment.Bottom,
+                    HorizontalAlignment = HAlignment.Center,
                     Align = Label.AlignMode.Center,
                     FontOverride = _resourceCache.GetFont("/Fonts/NotoSansDisplay/NotoSansDisplay-Bold.ttf", 12),
                     FontColorOverride = Color.Gray,
@@ -365,14 +342,9 @@ namespace Content.Client.GameObjects.Components.Wires
                 LayoutContainer.SetPosition(wire, (2, 16));
 
                 ToolTip = color.Name();
+                MinSize = (20, 102);
             }
 
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return (20, 102);
-            }
-
-
             protected override void KeyBindDown(GUIBoundKeyEventArgs args)
             {
                 base.KeyBindDown(args);
@@ -425,7 +397,8 @@ namespace Content.Client.GameObjects.Components.Wires
 
                 private readonly IResourceCache _resourceCache;
 
-                public WireRender(WireColor color, bool isCut, bool flip, bool mirror, int type, IResourceCache resourceCache)
+                public WireRender(WireColor color, bool isCut, bool flip, bool mirror, int type,
+                    IResourceCache resourceCache)
                 {
                     _resourceCache = resourceCache;
                     _color = color;
@@ -433,11 +406,8 @@ namespace Content.Client.GameObjects.Components.Wires
                     _flip = flip;
                     _mirror = mirror;
                     _type = type;
-                }
 
-                protected override Vector2 CalculateMinimumSize()
-                {
-                    return (16, 50);
+                    SetSize = (16, 50);
                 }
 
                 protected override void Draw(DrawingHandleScreen handle)
@@ -529,6 +499,7 @@ namespace Content.Client.GameObjects.Components.Wires
 
                 var lightContainer = new Control
                 {
+                    SetSize = (20, 20),
                     Children =
                     {
                         new TextureRect
@@ -588,10 +559,10 @@ namespace Content.Client.GameObjects.Components.Wires
                     Text = data.Text,
                     FontOverride = font,
                     FontColorOverride = Color.FromHex("#A1A6AE"),
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    VerticalAlignment = VAlignment.Center,
                 });
                 hBox.AddChild(lightContainer);
-                hBox.AddChild(new Control {CustomMinimumSize = (6, 0)});
+                hBox.AddChild(new Control {MinSize = (6, 0)});
                 AddChild(hBox);
             }
         }
diff --git a/Content.Client/GameObjects/EntitySystems/DoAfter/DoAfterGui.cs b/Content.Client/GameObjects/EntitySystems/DoAfter/DoAfterGui.cs
index b7fb691d59..ce588b13b1 100644
--- a/Content.Client/GameObjects/EntitySystems/DoAfter/DoAfterGui.cs
+++ b/Content.Client/GameObjects/EntitySystems/DoAfter/DoAfterGui.cs
@@ -69,7 +69,7 @@ namespace Content.Client.GameObjects.EntitySystems.DoAfter
 
             var doAfterBar = new DoAfterBar
             {
-                SizeFlagsVertical = SizeFlags.ShrinkCenter
+                VerticalAlignment = VAlignment.Center
             };
 
             _doAfterBars[message.ID] = doAfterBar;
@@ -82,7 +82,7 @@ namespace Content.Client.GameObjects.EntitySystems.DoAfter
                     {
                         Texture = StaticIoC.ResC.GetTexture("/Textures/Interface/Misc/progress_bar.rsi/icon.png"),
                         TextureScale = Vector2.One * DoAfterBar.DoAfterBarScale,
-                        SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                        VerticalAlignment = VAlignment.Center,
                     },
 
                     doAfterBar
diff --git a/Content.Client/GameObjects/EntitySystems/ExamineSystem.cs b/Content.Client/GameObjects/EntitySystems/ExamineSystem.cs
index a0513e5788..63186bfa26 100644
--- a/Content.Client/GameObjects/EntitySystems/ExamineSystem.cs
+++ b/Content.Client/GameObjects/EntitySystems/ExamineSystem.cs
@@ -90,10 +90,11 @@ namespace Content.Client.GameObjects.EntitySystems
             hBox.AddChild(new Label
             {
                 Text = entity.Name,
-                SizeFlagsHorizontal = Control.SizeFlags.FillExpand,
+                HorizontalExpand = true,
             });
 
-            var size = Vector2.ComponentMax((minWidth, 0), panel.CombinedMinimumSize);
+            panel.Measure(Vector2.Infinity);
+            var size = Vector2.ComponentMax((minWidth, 0), panel.DesiredSize);
 
             _examineTooltipOpen.Open(UIBox2.FromDimensions(popupPos, size));
 
diff --git a/Content.Client/GameObjects/EntitySystems/HealthOverlay/HealthOverlayGui.cs b/Content.Client/GameObjects/EntitySystems/HealthOverlay/HealthOverlayGui.cs
index e56cc7078e..c38c390633 100644
--- a/Content.Client/GameObjects/EntitySystems/HealthOverlay/HealthOverlayGui.cs
+++ b/Content.Client/GameObjects/EntitySystems/HealthOverlay/HealthOverlayGui.cs
@@ -26,14 +26,14 @@ namespace Content.Client.GameObjects.EntitySystems.HealthOverlay
             CritBar = new HealthOverlayBar
             {
                 Visible = false,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                VerticalAlignment = VAlignment.Center,
                 Color = Color.Red
             };
 
             HealthBar = new HealthOverlayBar
             {
                 Visible = false,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                VerticalAlignment = VAlignment.Center,
                 Color = Color.Green
             };
 
@@ -45,7 +45,7 @@ namespace Content.Client.GameObjects.EntitySystems.HealthOverlay
                     {
                         Texture = StaticIoC.ResC.GetTexture("/Textures/Interface/Misc/health_bar.rsi/icon.png"),
                         TextureScale = Vector2.One * HealthOverlayBar.HealthBarScale,
-                        SizeFlagsVertical = SizeFlags.ShrinkCenter
+                        VerticalAlignment = VAlignment.Center,
                     },
                     CritBar,
                     HealthBar
diff --git a/Content.Client/GameObjects/EntitySystems/VerbSystem.cs b/Content.Client/GameObjects/EntitySystems/VerbSystem.cs
index 25ce6ae03d..9dbd60b6fe 100644
--- a/Content.Client/GameObjects/EntitySystems/VerbSystem.cs
+++ b/Content.Client/GameObjects/EntitySystems/VerbSystem.cs
@@ -164,7 +164,7 @@ namespace Content.Client.GameObjects.EntitySystems
                 {
                     _currentEntityList.List.AddChild(new PanelContainer
                     {
-                        CustomMinimumSize = (0, 2),
+                        MinSize = (0, 2),
                         PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#333")}
                     });
                 }
@@ -176,7 +176,8 @@ namespace Content.Client.GameObjects.EntitySystems
 
             _userInterfaceManager.ModalRoot.AddChild(_currentEntityList);
 
-            var size = _currentEntityList.List.CombinedMinimumSize;
+            _currentEntityList.List.Measure(Vector2.Infinity);
+            var size = _currentEntityList.List.DesiredSize;
             var box = UIBox2.FromDimensions(_userInterfaceManager.MousePositionScaled, size);
             _currentEntityList.Open(box);
 
@@ -284,7 +285,7 @@ namespace Content.Client.GameObjects.EntitySystems
                     {
                         vBox.AddChild(new PanelContainer
                         {
-                            CustomMinimumSize = (0, 2),
+                            MinSize = (0, 2),
                             PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#333")}
                         });
                     }
@@ -306,7 +307,7 @@ namespace Content.Client.GameObjects.EntitySystems
                         {
                             vBox.AddChild(new PanelContainer
                             {
-                                CustomMinimumSize = (0, 2),
+                                MinSize = (0, 2),
                                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#333")}
                             });
                         }
@@ -449,11 +450,11 @@ namespace Content.Client.GameObjects.EntitySystems
                 {
                     text = $"{text} ({entity.Uid})";
                 }
-                control.AddChild(new MarginContainer
+
+                control.AddChild(new Label
                 {
-                    MarginLeftOverride = 4,
-                    MarginRightOverride = 4,
-                    Children = {new Label {Text = text}}
+                    Margin = new Thickness(4, 0),
+                    Text = text
                 });
 
                 AddChild(control);
@@ -486,7 +487,8 @@ namespace Content.Client.GameObjects.EntitySystems
                     var func = args.Function;
                     var funcId = _master._inputManager.NetworkBindMap.KeyFunctionID(args.Function);
 
-                    var message = new FullInputCmdMessage(_master._gameTiming.CurTick, _master._gameTiming.TickFraction, funcId, BoundKeyState.Down,
+                    var message = new FullInputCmdMessage(_master._gameTiming.CurTick, _master._gameTiming.TickFraction,
+                        funcId, BoundKeyState.Down,
                         _entity.Transform.Coordinates,
                         args.PointerLocation, _entity.Uid);
 
@@ -546,12 +548,12 @@ namespace Content.Client.GameObjects.EntitySystems
                     {
                         (_icon = new TextureRect
                         {
-                            CustomMinimumSize = (32, 32),
+                            MinSize = (32, 32),
                             Stretch = TextureRect.StretchMode.KeepCentered
                         }),
                         (_label = new Label()),
                         // Padding
-                        new Control {CustomMinimumSize = (8, 0)}
+                        new Control {MinSize = (8, 0)}
                     }
                 });
             }
@@ -603,17 +605,17 @@ namespace Content.Client.GameObjects.EntitySystems
                     {
                         (_icon = new TextureRect
                         {
-                            CustomMinimumSize = (32, 32),
+                            MinSize = (32, 32),
                             Stretch = TextureRect.StretchMode.KeepCentered
                         }),
 
                         (_label = new Label
                         {
-                            SizeFlagsHorizontal = SizeFlags.FillExpand
+                            HorizontalExpand = true
                         }),
 
                         // Padding
-                        new Control {CustomMinimumSize = (8, 0)},
+                        new Control {MinSize = (8, 0)},
 
                         new TextureRect
                         {
@@ -662,7 +664,7 @@ namespace Content.Client.GameObjects.EntitySystems
                         {
                             popup.List.AddChild(new PanelContainer
                             {
-                                CustomMinimumSize = (0, 2),
+                                MinSize = (0, 2),
                                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#333")}
                             });
                         }
diff --git a/Content.Client/Instruments/InstrumentMenu.xaml b/Content.Client/Instruments/InstrumentMenu.xaml
index fb501e4a96..6cd7f78b55 100644
--- a/Content.Client/Instruments/InstrumentMenu.xaml
+++ b/Content.Client/Instruments/InstrumentMenu.xaml
@@ -1,21 +1,32 @@
-<SS14Window xmlns="https://spacestation14.io">
-    <MarginContainer Name="Margin" SizeFlagsVertical="FillExpand" SizeFlagsHorizontal="Fill">
-        <VBoxContainer SizeFlagsVertical="FillExpand" SizeFlagsHorizontal="FillExpand" SeparationOverride="5">
-            <HBoxContainer SizeFlagsVertical="FillExpand" SizeFlagsHorizontal="FillExpand">
-                <Button Name="InputButton" ToggleMode="True" Text="MIDI Input" TextAlign="Center" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="1"/>
-                <Control SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="2" />
-                <Button Name="FileButton" Text="Play MIDI File" TextAlign="Center" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="1"/>
-            </HBoxContainer>
-            <HBoxContainer SizeFlagsVertical="FillExpand" SizeFlagsHorizontal="Fill">
-                <Button Name="LoopButton" ToggleMode="True" Text="Loop" TextAlign="Center" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="1"/>
-                <Control SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="2" />
-                <Button Name="StopButton" Text="Stop" TextAlign="Center" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="1"/>
-            </HBoxContainer>
-            <HBoxContainer SizeFlagsVertical="ShrinkEnd" SizeFlagsHorizontal="FillExpand">
-                <Control SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.125"/>
-                <Slider Name="PlaybackSlider" SizeFlagsHorizontal="FillExpand" />
-                <Control SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.125"/>
-            </HBoxContainer>
-        </VBoxContainer>
-    </MarginContainer>
+<SS14Window xmlns="https://spacestation14.io"
+            xmlns:gfx="clr-namespace:Robust.Client.Graphics;assembly=Robust.Client">
+    <VBoxContainer SeparationOverride="5">
+        <HBoxContainer VerticalExpand="True">
+            <Button Name="InputButton" ToggleMode="True" Text="MIDI Input" TextAlign="Center"
+                    HorizontalExpand="True" SizeFlagsStretchRatio="1" />
+            <Control HorizontalExpand="True" SizeFlagsStretchRatio="2" />
+            <Button Name="FileButton" Text="Play MIDI File" TextAlign="Center" HorizontalExpand="True"
+                    SizeFlagsStretchRatio="1" />
+        </HBoxContainer>
+        <HBoxContainer VerticalExpand="True">
+            <Button Name="LoopButton" ToggleMode="True" Text="Loop" TextAlign="Center" HorizontalExpand="True"
+                    SizeFlagsStretchRatio="1" />
+            <Control HorizontalExpand="True" SizeFlagsStretchRatio="2" />
+            <Button Name="StopButton" Text="Stop" TextAlign="Center" HorizontalExpand="True"
+                    SizeFlagsStretchRatio="1" />
+        </HBoxContainer>
+        <HBoxContainer VerticalExpand="True">
+            <Control HorizontalExpand="True" SizeFlagsStretchRatio="0.125" />
+            <Slider Name="PlaybackSlider" HorizontalExpand="True" />
+            <Control HorizontalExpand="True" SizeFlagsStretchRatio="0.125" />
+        </HBoxContainer>
+    </VBoxContainer>
+    <PanelContainer Name="UnavailableOverlay" Visible="False" MouseFilter="Stop">
+        <PanelContainer.PanelOverride>
+            <gfx:StyleBoxFlat BackgroundColor="#000000E5" />
+        </PanelContainer.PanelOverride>
+        <Label VerticalAlignment="Center" HorizontalAlignment="Center" Align="Center"
+               StyleClasses="LabelBig"
+               Text="{Loc 'MIDI support is currently&#x0a;not available on your platform.'}" />
+    </PanelContainer>
 </SS14Window>
diff --git a/Content.Client/Instruments/InstrumentMenu.xaml.cs b/Content.Client/Instruments/InstrumentMenu.xaml.cs
index c31fea6874..e7a21a76ff 100644
--- a/Content.Client/Instruments/InstrumentMenu.xaml.cs
+++ b/Content.Client/Instruments/InstrumentMenu.xaml.cs
@@ -30,8 +30,6 @@ namespace Content.Client.Instruments
 
         private readonly InstrumentBoundUserInterface _owner;
 
-        protected override Vector2? CustomSize => (400, 150);
-
         public InstrumentMenu(InstrumentBoundUserInterface owner)
         {
             RobustXamlLoader.Load(this);
@@ -50,23 +48,7 @@ namespace Content.Client.Instruments
 
             if (!_midiManager.IsAvailable)
             {
-                Margin.AddChild(new PanelContainer
-                {
-                    MouseFilter = MouseFilterMode.Stop,
-                    PanelOverride = new StyleBoxFlat {BackgroundColor = Color.Black.WithAlpha(0.90f)},
-                    Children =
-                    {
-                        new Label
-                        {
-                            Align = Label.AlignMode.Center,
-                            SizeFlagsVertical = SizeFlags.ShrinkCenter,
-                            SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                            StyleClasses = {StyleNano.StyleClassLabelBig},
-                            Text = Loc.GetString("MIDI support is currently\nnot available on your platform.")
-                        }
-                    }
-                });
-
+                UnavailableOverlay.Visible = true;
                 // We return early as to not give the buttons behavior.
                 return;
             }
@@ -77,6 +59,8 @@ namespace Content.Client.Instruments
             StopButton.OnPressed += MidiStopButtonOnPressed;
             PlaybackSlider.OnValueChanged += PlaybackSliderSeek;
             PlaybackSlider.OnKeyBindUp += PlaybackSliderKeyUp;
+
+            MinSize = SetSize = (400, 150);
         }
 
         private void InstrumentOnMidiPlaybackEnded()
diff --git a/Content.Client/Research/LatheMenu.cs b/Content.Client/Research/LatheMenu.cs
index d419fb45a6..51f4ccc363 100644
--- a/Content.Client/Research/LatheMenu.cs
+++ b/Content.Client/Research/LatheMenu.cs
@@ -23,7 +23,6 @@ namespace Content.Client.Research
         public Button QueueButton;
         public Button ServerConnectButton;
         public Button ServerSyncButton;
-        protected override Vector2? CustomSize => (300, 450);
 
         public LatheBoundUserInterface Owner { get; set; }
 
@@ -31,28 +30,23 @@ namespace Content.Client.Research
 
         public LatheMenu(LatheBoundUserInterface owner = null)
         {
+            SetSize = MinSize = (300, 450);
             IoCManager.InjectDependencies(this);
 
             Owner = owner;
 
             Title = "Lathe Menu";
 
-            var margin = new MarginContainer()
-            {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-            };
-
             var vBox = new VBoxContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SeparationOverride = 5,
             };
 
             var hBoxButtons = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1,
             };
 
@@ -60,7 +54,6 @@ namespace Content.Client.Research
             {
                 Text = "Queue",
                 TextAlign = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.Fill,
                 SizeFlagsStretchRatio = 1,
             };
 
@@ -68,7 +61,6 @@ namespace Content.Client.Research
             {
                 Text = "Server list",
                 TextAlign = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.Fill,
                 SizeFlagsStretchRatio = 1,
             };
 
@@ -76,27 +68,26 @@ namespace Content.Client.Research
             {
                 Text = "Sync",
                 TextAlign = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.Fill,
                 SizeFlagsStretchRatio = 1,
             };
 
             var spacer = new Control()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 3,
             };
 
             var hBoxFilter = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1
             };
 
             _searchBar = new LineEdit()
             {
                 PlaceHolder = "Search Designs",
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 3
             };
 
@@ -106,7 +97,6 @@ namespace Content.Client.Research
             {
                 Text = "Filter",
                 TextAlign = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.Fill,
                 SizeFlagsStretchRatio = 1,
                 Disabled = true,
             };
@@ -114,7 +104,7 @@ namespace Content.Client.Research
             _items = new ItemList()
             {
                 SizeFlagsStretchRatio = 8,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SelectMode = ItemList.ItemListSelectMode.Button,
             };
 
@@ -124,14 +114,14 @@ namespace Content.Client.Research
             {
                 PlaceHolder = "Amount",
                 Text = "1",
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
             };
 
             _amountLineEdit.OnTextChanged += PopulateDisabled;
 
             _materials = new ItemList()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 3
             };
 
@@ -153,9 +143,7 @@ namespace Content.Client.Research
             vBox.AddChild(_amountLineEdit);
             vBox.AddChild(_materials);
 
-            margin.AddChild(vBox);
-
-            Contents.AddChild(margin);
+            Contents.AddChild(vBox);
         }
 
         public void ItemSelected(ItemList.ItemListSelectedEventArgs args)
diff --git a/Content.Client/Research/LatheQueueMenu.cs b/Content.Client/Research/LatheQueueMenu.cs
index 1f619281d4..d8ddf981d2 100644
--- a/Content.Client/Research/LatheQueueMenu.cs
+++ b/Content.Client/Research/LatheQueueMenu.cs
@@ -4,15 +4,13 @@ using Robust.Client.Graphics;
 using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
 using Robust.Client.Utility;
-using Robust.Shared.Maths;
+using Robust.Shared.Localization;
 using Robust.Shared.ViewVariables;
 
 namespace Content.Client.Research
 {
     public class LatheQueueMenu : SS14Window
     {
-        protected override Vector2? CustomSize => (300, 450);
-
         public LatheBoundUserInterface Owner { get; set; }
 
         [ViewVariables]
@@ -23,67 +21,45 @@ namespace Content.Client.Research
 
         public LatheQueueMenu()
         {
-                        Title = "Lathe Queue";
-
-            var margin = new MarginContainer()
-            {
-                /*MarginTop = 5f,
-                MarginLeft = 5f,
-                MarginRight = -5f,
-                MarginBottom = -5f,*/
-            };
-
-//            margin.SetAnchorAndMarginPreset(LayoutPreset.Wide);
+            SetSize = MinSize = (300, 450);
+            Title = Loc.GetString("Lathe Queue");
 
             var vBox = new VBoxContainer();
 
-  //          vBox.SetAnchorAndMarginPreset(LayoutPreset.Wide);
-
-            var descMargin = new MarginContainer()
-            {
-                /*MarginTop = 5f,
-                MarginLeft = 5f,
-                MarginRight = -5f,
-                MarginBottom = -5f,*/
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsStretchRatio = 2,
-            };
-
             var hBox = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                SizeFlagsStretchRatio = 2,
             };
 
             _icon = new TextureRect()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 2,
             };
 
             var vBoxInfo = new VBoxContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 3,
             };
 
             _nameLabel = new Label()
             {
                 RectClipContent = true,
-                SizeFlagsHorizontal = SizeFlags.Fill,
             };
 
             _description = new Label()
             {
                 RectClipContent = true,
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.Fill,
+                VerticalAlignment = VAlignment.Stretch,
+                VerticalExpand = true
 
             };
 
             _queueList = new ItemList()
             {
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 3,
                 SelectMode = ItemList.ItemListSelectMode.None
             };
@@ -94,14 +70,10 @@ namespace Content.Client.Research
             hBox.AddChild(_icon);
             hBox.AddChild(vBoxInfo);
 
-            descMargin.AddChild(hBox);
-
-            vBox.AddChild(descMargin);
+            vBox.AddChild(hBox);
             vBox.AddChild(_queueList);
 
-            margin.AddChild(vBox);
-
-            Contents.AddChild(margin);
+            Contents.AddChild(vBox);
 
             ClearInfo();
         }
diff --git a/Content.Client/Research/ResearchConsoleMenu.cs b/Content.Client/Research/ResearchConsoleMenu.cs
index e1b6da589a..2db8b37769 100644
--- a/Content.Client/Research/ResearchConsoleMenu.cs
+++ b/Content.Client/Research/ResearchConsoleMenu.cs
@@ -16,8 +16,6 @@ namespace Content.Client.Research
     {
         public ResearchConsoleBoundUserInterface Owner { get; set; }
 
-        protected override Vector2? CustomSize => (800, 400);
-
         private readonly List<TechnologyPrototype> _unlockedTechnologyPrototypes = new();
         private readonly List<TechnologyPrototype> _unlockableTechnologyPrototypes = new();
         private readonly List<TechnologyPrototype> _futureTechnologyPrototypes = new();
@@ -40,6 +38,8 @@ namespace Content.Client.Research
 
         public ResearchConsoleMenu(ResearchConsoleBoundUserInterface owner = null)
         {
+            SetSize = MinSize = (800, 400);
+
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("R&D Console");
@@ -49,8 +49,8 @@ namespace Content.Client.Research
             _unlockedTechnologies = new ItemList()
             {
                 SelectMode = ItemList.ItemListSelectMode.Button,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
             };
 
             _unlockedTechnologies.OnItemSelected += UnlockedTechnologySelected;
@@ -58,8 +58,8 @@ namespace Content.Client.Research
             _unlockableTechnologies = new ItemList()
             {
                 SelectMode = ItemList.ItemListSelectMode.Button,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
             };
 
             _unlockableTechnologies.OnItemSelected += UnlockableTechnologySelected;
@@ -67,44 +67,44 @@ namespace Content.Client.Research
             _futureTechnologies = new ItemList()
             {
                 SelectMode = ItemList.ItemListSelectMode.Button,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
             };
 
             _futureTechnologies.OnItemSelected += FutureTechnologySelected;
 
             var vbox = new VBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
             };
 
             var hboxTechnologies = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 2,
                 SeparationOverride = 10,
             };
 
             var hboxSelected = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1
             };
 
             var vboxPoints =  new VBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1,
             };
 
             var vboxTechInfo = new VBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 3,
             };
 
@@ -114,8 +114,8 @@ namespace Content.Client.Research
             var vboxPointsButtons = new VBoxContainer()
             {
                 Align = BoxContainer.AlignMode.End,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
             };
 
             ServerSelectionButton = new Button() { Text = Loc.GetString("Server list") };
@@ -133,8 +133,8 @@ namespace Content.Client.Research
 
             _technologyIcon = new TextureRect()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1,
                 Stretch = TextureRect.StretchMode.KeepAspectCentered,
             };
diff --git a/Content.Client/State/LauncherConnecting.cs b/Content.Client/State/LauncherConnecting.cs
index cffb9ca35f..61c3cc19a0 100644
--- a/Content.Client/State/LauncherConnecting.cs
+++ b/Content.Client/State/LauncherConnecting.cs
@@ -46,31 +46,26 @@ namespace Content.Client.State
                     new VBoxContainer
                     {
                         SeparationOverride = 0,
-                        CustomMinimumSize = (300, 200),
+                        MinSize = (300, 200),
                         Children =
                         {
                             new HBoxContainer
                             {
                                 Children =
                                 {
-                                    new MarginContainer
+                                    new Label
                                     {
-                                        MarginLeftOverride = 8,
-                                        Children =
-                                        {
-                                            new Label
-                                            {
-                                                Text = Loc.GetString("Space Station 14"),
-                                                StyleClasses = {StyleBase.StyleClassLabelHeading},
-                                                VAlign = Label.VAlignMode.Center
-                                            },
-                                        }
+                                        Margin = new Thickness(8, 0, 0, 0),
+                                        Text = Loc.GetString("Space Station 14"),
+                                        StyleClasses = {StyleBase.StyleClassLabelHeading},
+                                        VAlign = Label.VAlignMode.Center
                                     },
 
                                     (exitButton = new Button
                                     {
                                         Text = Loc.GetString("Exit"),
-                                        SizeFlagsHorizontal = Control.SizeFlags.ShrinkEnd | Control.SizeFlags.Expand
+                                        HorizontalAlignment = Control.HAlignment.Right,
+                                        HorizontalExpand = true,
                                     }),
                                 }
                             },
@@ -78,103 +73,93 @@ namespace Content.Client.State
                             // Line
                             new HighDivider(),
 
-                            new MarginContainer
+                            new VBoxContainer
                             {
-                                SizeFlagsVertical = Control.SizeFlags.FillExpand,
-                                MarginLeftOverride = 4,
-                                MarginRightOverride = 4,
-                                MarginTopOverride = 4,
+                                VerticalExpand = true,
+                                Margin = new Thickness(4, 4, 4, 0),
+                                SeparationOverride = 0,
                                 Children =
                                 {
-                                    new VBoxContainer
+                                    new Control
                                     {
-                                        SeparationOverride = 0,
+                                        VerticalExpand = true,
                                         Children =
                                         {
-                                            new Control
+                                            (_connectingStatus = new VBoxContainer
                                             {
-                                                SizeFlagsVertical = Control.SizeFlags.FillExpand,
+                                                SeparationOverride = 0,
                                                 Children =
                                                 {
-                                                    (_connectingStatus = new VBoxContainer
+                                                    new Label
                                                     {
-                                                        SeparationOverride = 0,
-                                                        Children =
-                                                        {
-                                                            new Label
-                                                            {
-                                                                Text = Loc.GetString("Connecting to server..."),
-                                                                Align = Label.AlignMode.Center,
-                                                            },
+                                                        Text = Loc.GetString("Connecting to server..."),
+                                                        Align = Label.AlignMode.Center,
+                                                    },
 
-                                                            (_connectStatus = new Label
-                                                            {
-                                                                StyleClasses = {StyleBase.StyleClassLabelSubText},
-                                                                Align = Label.AlignMode.Center,
-                                                            }),
-                                                        }
+                                                    (_connectStatus = new Label
+                                                    {
+                                                        StyleClasses = {StyleBase.StyleClassLabelSubText},
+                                                        Align = Label.AlignMode.Center,
                                                     }),
-                                                    (_connectFail = new VBoxContainer
+                                                }
+                                            }),
+                                            (_connectFail = new VBoxContainer
+                                            {
+                                                Visible = false,
+                                                SeparationOverride = 0,
+                                                Children =
+                                                {
+                                                    (_connectFailReason = new Label
                                                     {
-                                                        Visible = false,
-                                                        SeparationOverride = 0,
-                                                        Children =
-                                                        {
-                                                            (_connectFailReason = new Label
-                                                            {
-                                                                Align = Label.AlignMode.Center
-                                                            }),
-
-                                                            (retryButton = new Button
-                                                            {
-                                                                Text = "Retry",
-                                                                SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter,
-                                                                SizeFlagsVertical =
-                                                                    Control.SizeFlags.Expand |
-                                                                    Control.SizeFlags.ShrinkEnd
-                                                            })
-                                                        }
+                                                        Align = Label.AlignMode.Center
                                                     }),
 
-                                                    (_disconnected = new VBoxContainer
+                                                    (retryButton = new Button
                                                     {
-                                                        SeparationOverride = 0,
-                                                        Children =
-                                                        {
-                                                            new Label
-                                                            {
-                                                                Text = "Disconnected from server:",
-                                                                Align = Label.AlignMode.Center
-                                                            },
-                                                            new Label
-                                                            {
-                                                                Text = _baseClient.LastDisconnectReason,
-                                                                Align = Label.AlignMode.Center
-                                                            },
-                                                            (reconnectButton = new Button
-                                                            {
-                                                                Text = "Reconnect",
-                                                                SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter,
-                                                                SizeFlagsVertical =
-                                                                    Control.SizeFlags.Expand |
-                                                                    Control.SizeFlags.ShrinkEnd
-                                                            })
-                                                        }
+                                                        Text = "Retry",
+                                                        HorizontalAlignment = Control.HAlignment.Center,
+                                                        VerticalExpand = true,
+                                                        VerticalAlignment = Control.VAlignment.Bottom,
                                                     })
                                                 }
-                                            },
+                                            }),
 
-                                            // Padding.
-                                            new Control {CustomMinimumSize = (0, 8)},
-
-                                            new Label
+                                            (_disconnected = new VBoxContainer
                                             {
-                                                Text = address,
-                                                StyleClasses = {StyleBase.StyleClassLabelSubText},
-                                                SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter,
-                                            }
+                                                SeparationOverride = 0,
+                                                Children =
+                                                {
+                                                    new Label
+                                                    {
+                                                        Text = "Disconnected from server:",
+                                                        Align = Label.AlignMode.Center
+                                                    },
+                                                    new Label
+                                                    {
+                                                        Text = _baseClient.LastDisconnectReason,
+                                                        Align = Label.AlignMode.Center
+                                                    },
+                                                    (reconnectButton = new Button
+                                                    {
+                                                        Text = "Reconnect",
+                                                        HorizontalAlignment = Control.HAlignment.Center,
+                                                        VerticalExpand = true,
+                                                        VerticalAlignment = Control.VAlignment.Bottom,
+                                                    })
+                                                }
+                                            })
                                         }
                                     },
+
+                                    // Padding.
+                                    new Control {MinSize = (0, 8)},
+
+                                    new Label
+                                    {
+                                        Text = address,
+                                        StyleClasses = {StyleBase.StyleClassLabelSubText},
+                                        HorizontalAlignment = Control.HAlignment.Center
+                                    }
                                 }
                             },
 
@@ -187,31 +172,23 @@ namespace Content.Client.State
                                     ContentMarginTopOverride = 2
                                 },
                             },
-
-                            new MarginContainer
+                            new HBoxContainer
                             {
-                                MarginLeftOverride = 12,
-                                MarginRightOverride = 4,
+                                Margin = new Thickness(12, 0, 4, 0),
+                                VerticalAlignment = Control.VAlignment.Bottom,
                                 Children =
                                 {
-                                    new HBoxContainer
+                                    new Label
                                     {
-                                        SizeFlagsVertical = Control.SizeFlags.ShrinkEnd,
-                                        Children =
-                                        {
-                                            new Label
-                                            {
-                                                Text = Loc.GetString("Don't die!"),
-                                                StyleClasses = {StyleBase.StyleClassLabelSubText}
-                                            },
-                                            new Label
-                                            {
-                                                Text = "ver 0.1",
-                                                SizeFlagsHorizontal =
-                                                    Control.SizeFlags.Expand | Control.SizeFlags.ShrinkEnd,
-                                                StyleClasses = {StyleBase.StyleClassLabelSubText}
-                                            }
-                                        }
+                                        Text = Loc.GetString("Don't die!"),
+                                        StyleClasses = {StyleBase.StyleClassLabelSubText}
+                                    },
+                                    new Label
+                                    {
+                                        Text = "ver 0.1",
+                                        HorizontalExpand = true,
+                                        HorizontalAlignment = Control.HAlignment.Right,
+                                        StyleClasses = {StyleBase.StyleClassLabelSubText}
                                     }
                                 }
                             },
diff --git a/Content.Client/State/MainMenu.cs b/Content.Client/State/MainMenu.cs
index 8d48cd2147..cc55b96f24 100644
--- a/Content.Client/State/MainMenu.cs
+++ b/Content.Client/State/MainMenu.cs
@@ -249,7 +249,7 @@ namespace Content.Client.State
                 UserNameBox = new LineEdit
                 {
                     Text = currentUserName, PlaceHolder = "Username",
-                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                    HorizontalExpand = true
                 };
 
                 userNameHBox.AddChild(UserNameBox);
@@ -268,13 +268,13 @@ namespace Content.Client.State
                 vBox.AddChild(JoinPublicServerButton);
 
                 // Separator.
-                vBox.AddChild(new Control {CustomMinimumSize = (0, 2)});
+                vBox.AddChild(new Control {MinSize = (0, 2)});
 
                 AddressBox = new LineEdit
                 {
                     Text = "localhost",
                     PlaceHolder = "server address:port",
-                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                    HorizontalExpand = true
                 };
 
                 vBox.AddChild(AddressBox);
@@ -289,7 +289,7 @@ namespace Content.Client.State
                 vBox.AddChild(DirectConnectButton);
 
                 // Separator.
-                vBox.AddChild(new Control {CustomMinimumSize = (0, 2)});
+                vBox.AddChild(new Control {MinSize = (0, 2)});
 
                 OptionsButton = new Button
                 {
diff --git a/Content.Client/UserInterface/ActionMenu.cs b/Content.Client/UserInterface/ActionMenu.cs
index a58263bbd4..2cdbb6fa65 100644
--- a/Content.Client/UserInterface/ActionMenu.cs
+++ b/Content.Client/UserInterface/ActionMenu.cs
@@ -68,7 +68,7 @@ namespace Content.Client.UserInterface
             _gameHud = IoCManager.Resolve<IGameHud>();
 
             Title = Loc.GetString("Actions");
-            CustomMinimumSize = (300, 300);
+            MinSize = (300, 300);
 
             Contents.AddChild(new VBoxContainer
             {
@@ -81,7 +81,7 @@ namespace Content.Client.UserInterface
                             (_searchBar = new LineEdit
                             {
                                 StyleClasses = { StyleNano.StyleClassActionSearchBox },
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                HorizontalExpand = true,
                                 PlaceHolder = Loc.GetString("Search")
                             }),
                             (_filterButton = new MultiselectOptionButton<string>()
@@ -97,14 +97,14 @@ namespace Content.Client.UserInterface
                     (_filterLabel = new Label()),
                     new ScrollContainer
                     {
-                        //TODO: needed? CustomMinimumSize = new Vector2(200.0f, 0.0f),
-                        SizeFlagsVertical = SizeFlags.FillExpand,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand,
+                        //TODO: needed? MinSize = new Vector2(200.0f, 0.0f),
+                        VerticalExpand = true,
+                        HorizontalExpand = true,
                         Children =
                         {
                             (_resultsGrid = new GridContainer
                             {
-                                MaxWidth = 300
+                                MaxGridWidth = 300
                             })
                         }
                     }
@@ -136,12 +136,12 @@ namespace Content.Client.UserInterface
 
             _dragShadow = new TextureRect
             {
-                CustomMinimumSize = (64, 64),
+                MinSize = (64, 64),
                 Stretch = TextureRect.StretchMode.Scale,
-                Visible = false
+                Visible = false,
+                SetSize = (64, 64)
             };
             UserInterfaceManager.PopupRoot.AddChild(_dragShadow);
-            LayoutContainer.SetSize(_dragShadow, (64, 64));
 
             _dragDropHelper = new DragDropHelper<ActionMenuItem>(OnBeginActionDrag, OnContinueActionDrag, OnEndActionDrag);
         }
@@ -190,7 +190,7 @@ namespace Content.Client.UserInterface
             base.Resized();
             // TODO: Can rework this once https://github.com/space-wizards/RobustToolbox/issues/1392 is done,
             // currently no good way to let the grid know what size it has to "work with", so must manually resize
-            _resultsGrid.MaxWidth = Width;
+            _resultsGrid.MaxGridWidth = Width;
         }
 
         private bool OnBeginActionDrag()
diff --git a/Content.Client/UserInterface/ActionMenuItem.cs b/Content.Client/UserInterface/ActionMenuItem.cs
index 2b03119eb6..40bf8f83ae 100644
--- a/Content.Client/UserInterface/ActionMenuItem.cs
+++ b/Content.Client/UserInterface/ActionMenuItem.cs
@@ -27,13 +27,13 @@ namespace Content.Client.UserInterface
             _onControlFocusExited = onControlFocusExited;
             Action = action;
 
-            CustomMinimumSize = (64, 64);
-            SizeFlagsVertical = SizeFlags.None;
+            MinSize = (64, 64);
+            VerticalAlignment = VAlignment.Top;
 
             AddChild(new TextureRect
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 Stretch = TextureRect.StretchMode.Scale,
                 Texture = action.Icon.Frame0()
             });
diff --git a/Content.Client/UserInterface/ActionsUI.cs b/Content.Client/UserInterface/ActionsUI.cs
index 86b07a3469..59b1a982bd 100644
--- a/Content.Client/UserInterface/ActionsUI.cs
+++ b/Content.Client/UserInterface/ActionsUI.cs
@@ -16,7 +16,6 @@ using Robust.Shared.Input;
 using Robust.Shared.Input.Binding;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
-using Robust.Shared.Maths;
 using Robust.Shared.Timing;
 
 namespace Content.Client.UserInterface
@@ -75,6 +74,7 @@ namespace Content.Client.UserInterface
 
         public ActionsUI(ClientActionsComponent actionsComponent)
         {
+            SetValue(LayoutContainer.DebugProperty, true);
             _actionsComponent = actionsComponent;
             _actionManager = IoCManager.Resolve<ActionManager>();
             _entityManager = IoCManager.Resolve<IEntityManager>();
@@ -83,14 +83,14 @@ namespace Content.Client.UserInterface
             _menu = new ActionMenu(_actionsComponent, this);
 
             LayoutContainer.SetGrowHorizontal(this, LayoutContainer.GrowDirection.End);
-            LayoutContainer.SetGrowVertical(this, LayoutContainer.GrowDirection.End);
+            LayoutContainer.SetGrowVertical(this, LayoutContainer.GrowDirection.Constrain);
             LayoutContainer.SetAnchorTop(this, 0f);
             LayoutContainer.SetAnchorBottom(this, 0.8f);
             LayoutContainer.SetMarginLeft(this, 13);
             LayoutContainer.SetMarginTop(this, 110);
 
-            SizeFlagsHorizontal = SizeFlags.None;
-            SizeFlagsVertical = SizeFlags.FillExpand;
+            HorizontalAlignment = HAlignment.Left;
+            VerticalExpand = true;
 
             var resourceCache = IoCManager.Resolve<IResourceCache>();
 
@@ -101,101 +101,101 @@ namespace Content.Client.UserInterface
             var panelContainer = new PanelContainer()
             {
                 StyleClasses = {StyleNano.StyleClassHotbarPanel},
-                SizeFlagsHorizontal = SizeFlags.None,
-                SizeFlagsVertical = SizeFlags.None
+                HorizontalAlignment = HAlignment.Left,
+                VerticalAlignment = VAlignment.Top
             };
             AddChild(panelContainer);
 
             var hotbarContainer = new VBoxContainer
             {
                 SeparationOverride = 3,
-                SizeFlagsHorizontal = SizeFlags.None
+                HorizontalAlignment = HAlignment.Left
             };
             panelContainer.AddChild(hotbarContainer);
 
             var settingsContainer = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
             hotbarContainer.AddChild(settingsContainer);
 
-            settingsContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 1 });
+            settingsContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 1 });
             _lockTexture = resourceCache.GetTexture("/Textures/Interface/Nano/lock.svg.192dpi.png");
             _unlockTexture = resourceCache.GetTexture("/Textures/Interface/Nano/lock_open.svg.192dpi.png");
             _lockButton = new TextureButton
             {
                 TextureNormal = _unlockTexture,
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1,
                 Scale = (0.5f, 0.5f)
             };
             settingsContainer.AddChild(_lockButton);
-            settingsContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 2 });
+            settingsContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 2 });
             _settingsButton = new TextureButton
             {
                 TextureNormal = resourceCache.GetTexture("/Textures/Interface/Nano/gear.svg.192dpi.png"),
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1,
                 Scale = (0.5f, 0.5f)
             };
             settingsContainer.AddChild(_settingsButton);
-            settingsContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 1 });
+            settingsContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 1 });
 
             // this allows a 2 column layout if window gets too small
             _slotContainer = new GridContainer
             {
-                MaxHeight = CalcMaxHeight()
+                MaxGridHeight = CalcMaxHeight()
             };
             hotbarContainer.AddChild(_slotContainer);
 
             _loadoutContainer = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 MouseFilter = MouseFilterMode.Stop
             };
             hotbarContainer.AddChild(_loadoutContainer);
 
-            _loadoutContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 1 });
+            _loadoutContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 1 });
             var previousHotbarIcon = new TextureRect()
             {
                 Texture = resourceCache.GetTexture("/Textures/Interface/Nano/left_arrow.svg.192dpi.png"),
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1,
                 TextureScale = (0.5f, 0.5f)
             };
             _loadoutContainer.AddChild(previousHotbarIcon);
-            _loadoutContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 2 });
+            _loadoutContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 2 });
             _loadoutNumber = new Label
             {
                 Text = "1",
                 SizeFlagsStretchRatio = 1
             };
             _loadoutContainer.AddChild(_loadoutNumber);
-            _loadoutContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 2 });
+            _loadoutContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 2 });
             var nextHotbarIcon = new TextureRect
             {
                 Texture = resourceCache.GetTexture("/Textures/Interface/Nano/right_arrow.svg.192dpi.png"),
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1,
                 TextureScale = (0.5f, 0.5f)
             };
             _loadoutContainer.AddChild(nextHotbarIcon);
-            _loadoutContainer.AddChild(new Control { SizeFlagsHorizontal = SizeFlags.FillExpand, SizeFlagsStretchRatio = 1 });
+            _loadoutContainer.AddChild(new Control { HorizontalExpand = true, SizeFlagsStretchRatio = 1 });
 
             _slots = new ActionSlot[ClientActionsComponent.Slots];
 
             _dragShadow = new TextureRect
             {
-                CustomMinimumSize = (64, 64),
+                MinSize = (64, 64),
                 Stretch = TextureRect.StretchMode.Scale,
-                Visible = false
+                Visible = false,
+                SetSize = (64, 64)
             };
             UserInterfaceManager.PopupRoot.AddChild(_dragShadow);
-            LayoutContainer.SetSize(_dragShadow, (64, 64));
 
             for (byte i = 0; i < ClientActionsComponent.Slots; i++)
             {
@@ -205,6 +205,8 @@ namespace Content.Client.UserInterface
             }
 
             DragDropHelper = new DragDropHelper<ActionSlot>(OnBeginActionDrag, OnContinueActionDrag, OnEndActionDrag);
+
+            MinSize = (10, 400);
         }
 
         protected override void EnteredTree()
@@ -231,16 +233,10 @@ namespace Content.Client.UserInterface
             _gameHud.ActionsButtonVisible = false;
         }
 
-        protected override Vector2 CalculateMinimumSize()
-        {
-            // allows us to shrink down to a 2-column layout minimum
-            return (10, 400);
-        }
-
         protected override void Resized()
         {
             base.Resized();
-            _slotContainer.MaxHeight = CalcMaxHeight();
+            _slotContainer.MaxGridHeight = CalcMaxHeight();
         }
 
         private float CalcMaxHeight()
@@ -265,7 +261,7 @@ namespace Content.Client.UserInterface
 
         protected override void UIScaleChanged()
         {
-            _slotContainer.MaxHeight = CalcMaxHeight();
+            _slotContainer.MaxGridHeight = CalcMaxHeight();
             base.UIScaleChanged();
         }
 
diff --git a/Content.Client/UserInterface/AdminAddReagentUI.cs b/Content.Client/UserInterface/AdminAddReagentUI.cs
index 1a7cab3114..e7d41b9ca9 100644
--- a/Content.Client/UserInterface/AdminAddReagentUI.cs
+++ b/Content.Client/UserInterface/AdminAddReagentUI.cs
@@ -82,11 +82,11 @@ namespace Content.Client.UserInterface
                                 (_amountEdit = new LineEdit
                                 {
                                     PlaceHolder = Loc.GetString("A number..."),
-                                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                                    HorizontalExpand = true
                                 }),
                             },
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
-                            SizeFlagsVertical = SizeFlags.FillExpand
+                            HorizontalExpand = true,
+                            VerticalExpand = true
                         },
                         new HBoxContainer
                         {
@@ -94,7 +94,7 @@ namespace Content.Client.UserInterface
                             {
                                 (_errorLabel = new Label
                                 {
-                                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                    HorizontalExpand = true,
                                     ClipText = true
                                 }),
 
diff --git a/Content.Client/UserInterface/AdminMenu/AdminMenuWindow.xaml.cs b/Content.Client/UserInterface/AdminMenu/AdminMenuWindow.xaml.cs
index a0f3e824f2..dc00852f5c 100644
--- a/Content.Client/UserInterface/AdminMenu/AdminMenuWindow.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/AdminMenuWindow.xaml.cs
@@ -21,10 +21,9 @@ namespace Content.Client.UserInterface.AdminMenu
             remove => PlayerTabControl.OnPlayerListRefresh -= value;
         }
 
-        protected override Vector2? CustomSize => (500, 250);
-
         public AdminMenuWindow()
         {
+            MinSize = SetSize = (500, 250);
             Title = Loc.GetString("Admin Menu");
             RobustXamlLoader.Load(this);
             IoCManager.InjectDependencies(this);
diff --git a/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml b/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml
index 594f9e7cdf..6cdafeb1c8 100644
--- a/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml
+++ b/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml
@@ -1,15 +1,15 @@
 <SS14Window
     xmlns="https://spacestation14.io">
-    <HBoxContainer SizeFlagsHorizontal="FillExpand">
-        <VBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.45">
-            <HBoxContainer SizeFlagsHorizontal="FillExpand" SizeFlagsVertical="FillExpand"
+    <HBoxContainer HorizontalExpand="True">
+        <VBoxContainer HorizontalExpand="True" SizeFlagsStretchRatio="0.45">
+            <HBoxContainer HorizontalExpand="True" VerticalExpand="True"
                                     SizeFlagsStretchRatio="0.1">
-                <LineEdit Name="SearchBar" PlaceHolder="Search" SizeFlagsHorizontal="FillExpand"
+                <LineEdit Name="SearchBar" PlaceHolder="Search" HorizontalExpand="True"
                                    SizeFlagsStretchRatio="0.6" />
             </HBoxContainer>
-            <ItemList Name="OutfitList" SelectMode="Single" SizeFlagsVertical="FillExpand"
+            <ItemList Name="OutfitList" SelectMode="Single" VerticalExpand="True"
                                SizeFlagsStretchRatio="0.9" />
-            <Button Name="ConfirmButton" SizeFlagsHorizontal="FillExpand" />
+            <Button Name="ConfirmButton" HorizontalExpand="True" />
         </VBoxContainer>
     </HBoxContainer>
 </SS14Window>
diff --git a/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml.cs b/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml.cs
index 2259127557..4a22d467f0 100644
--- a/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/SetOutfit/SetOutfitMenu.xaml.cs
@@ -20,12 +20,11 @@ namespace Content.Client.UserInterface.AdminMenu.SetOutfit
         [Dependency] private readonly IClientConsoleHost _consoleHost = default!;
 
         public EntityUid? TargetEntityId { get; set; }
-        protected override Vector2? CustomSize => (250, 320);
-
         private StartingGearPrototype? _selectedOutfit;
 
         public SetOutfitMenu()
         {
+            MinSize = SetSize = (250, 320);
             IoCManager.InjectDependencies(this);
             RobustXamlLoader.Load(this);
 
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml
index c037f0cd1a..15fcc606d5 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml
@@ -1,12 +1,10 @@
-<MarginContainer
+<Control
     xmlns="https://spacestation14.io"
     xmlns:amc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:at="clr-namespace:Content.Client.UserInterface.AdminMenu.Tabs.AdminTab"
-    MarginLeftOverride="4"
-    MarginTopOverride="4" MarginRightOverride="4"
-    MarginBottomOverride="4"
-    CustomMinimumSize="50 50">
+    Margin="4"
+    MinSize="50 50">
     <VBoxContainer>
         <GridContainer Columns="4">
             <amc:UICommandButton Command="kick" Text="{Loc Kick}" WindowType="{x:Type at:KickWindow}" />
@@ -16,4 +14,4 @@
             <amc:CommandButton Command="permissions" Text="{Loc Permissions Panel}" />
         </GridContainer>
     </VBoxContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml.cs
index 2a60a2ec2c..3bed8b059e 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/AdminTab.xaml.cs
@@ -1,11 +1,11 @@
 #nullable enable
 using Robust.Client.AutoGenerated;
-using Robust.Client.UserInterface.Controls;
+using Robust.Client.UserInterface;
 
 namespace Content.Client.UserInterface.AdminMenu.Tabs.AdminTab
 {
     [GenerateTypedNameReferences]
-    public partial class AdminTab : MarginContainer
+    public partial class AdminTab : Control
     {
     }
 }
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/BanWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/BanWindow.xaml
index 4d2d583b79..c228b2dd28 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/BanWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/BanWindow.xaml
@@ -1,24 +1,24 @@
 <SS14Window
     xmlns="https://spacestation14.io"
     xmlns:cc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
-    Title="{Loc Ban}" CustomMinimumSize="425 162">
+    Title="{Loc Ban}" MinSize="425 162">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Player}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <LineEdit Name="PlayerNameLine" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Player}" MinWidth="100" />
+            <Control MinWidth="50" />
+            <LineEdit Name="PlayerNameLine" MinWidth="100" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Reason}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <LineEdit Name="ReasonLine" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Reason}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <LineEdit Name="ReasonLine" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Minutes}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <LineEdit Name="MinutesLine" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" PlaceHolder="{Loc 0 minutes for a permanent ban}" />
+            <Label Text="{Loc Minutes}" MinWidth="100" />
+            <Control MinWidth="50" />
+            <LineEdit Name="MinutesLine" MinWidth="100" HorizontalExpand="True" PlaceHolder="{Loc 0 minutes for a permanent ban}" />
         </HBoxContainer>
-        <Control CustomMinimumSize="50 0" />
+        <Control MinWidth="50" />
         <Button Name="SubmitButton" Text="{Loc Ban}" />
     </VBoxContainer>
 </SS14Window>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/KickWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/KickWindow.xaml
index be57f409b8..6c880ef553 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/KickWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/KickWindow.xaml
@@ -1,12 +1,12 @@
 <SS14Window
     xmlns="https://spacestation14.io"
     xmlns:cc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
-    Title="{Loc Kick}" CustomMinimumSize="425 272">
+    Title="{Loc Kick}" MinSize="425 272">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Reason}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <LineEdit Name="ReasonLine" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Reason}" MinWidth="100" />
+            <Control MinWidth="50" />
+            <LineEdit Name="ReasonLine" MinWidth="100" HorizontalExpand="True" />
         </HBoxContainer>
         <cc:PlayerListControl Name="PlayerList" />
         <Button Name="SubmitButton" Text="{Loc Kick}" />
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/TeleportWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/TeleportWindow.xaml
index 9fa6ac12d5..892329c03d 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/TeleportWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminTab/TeleportWindow.xaml
@@ -1,8 +1,8 @@
 <SS14Window
     xmlns="https://spacestation14.io"
     xmlns:cc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
-    Title="{Loc Teleport}" CustomMinimumSize="425 230">
-    <VBoxContainer SizeFlagsVertical="FillExpand">
+    Title="{Loc Teleport}" MinSize="425 230">
+    <VBoxContainer>
         <cc:PlayerListControl Name="PlayerList" />
         <Button Name="SubmitButton" Text="{Loc Teleport}" />
     </VBoxContainer>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml
index 90bdd0e28a..f087377ed6 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml
@@ -1,16 +1,14 @@
-<MarginContainer
+<Control
     xmlns="https://spacestation14.io"
     xmlns:amc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:abt="clr-namespace:Content.Client.UserInterface.AdminMenu.Tabs.AdminbusTab"
-    MarginLeftOverride="4"
-    MarginTopOverride="4" MarginRightOverride="4"
-    MarginBottomOverride="4"
-    CustomMinimumSize="50 50">
+    Margin="4"
+    MinSize="50 50">
     <GridContainer
         Columns="4">
         <amc:CommandButton Name="SpawnEntitiesButton" Text="{Loc Spawn Entities}" />
         <amc:CommandButton Name="SpawnTilesButton" Text="{Loc Spawn Tiles} " />
         <amc:UICommandButton Command="events" Text="{Loc Station Events}" WindowType="{x:Type abt:StationEventsWindow}" />
     </GridContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml.cs
index ff4efddedb..b91579ed0c 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/AdminbusTab.xaml.cs
@@ -2,6 +2,7 @@
 using Robust.Client.AutoGenerated;
 using Robust.Client.Placement;
 using Robust.Client.ResourceManagement;
+using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
 using Robust.Shared.IoC;
@@ -11,7 +12,7 @@ using Robust.Shared.Prototypes;
 namespace Content.Client.UserInterface.AdminMenu.Tabs.AdminbusTab
 {
     [GenerateTypedNameReferences]
-    public partial class AdminbusTab : MarginContainer
+    public partial class AdminbusTab : Control
     {
         protected override void EnteredTree()
         {
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/StationEventsWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/StationEventsWindow.xaml
index e210a4a485..097eb0f150 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/StationEventsWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AdminbusTab/StationEventsWindow.xaml
@@ -2,9 +2,9 @@
     xmlns="https://spacestation14.io" Title="Kick">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Event}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="EventsOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Event}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="EventsOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <Button Name="PauseButton" Text="{Loc Pause}" />
         <Button Name="ResumeButton" Text="{Loc Resume}" />
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddAtmosWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddAtmosWindow.xaml
index fdbad06848..bdc9528ba8 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddAtmosWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddAtmosWindow.xaml
@@ -2,9 +2,9 @@
     xmlns="https://spacestation14.io" Title="{Loc Add Atmos}">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Grid}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GridOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Grid}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GridOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <Button Name="SubmitButton" Text="{Loc Add Atmos}" />
     </VBoxContainer>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddGasWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddGasWindow.xaml
index 3532123857..d31d48dd8c 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddGasWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AddGasWindow.xaml
@@ -2,29 +2,29 @@
     xmlns="https://spacestation14.io" Title="{Loc Add Gas}">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Grid}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GridOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Grid}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GridOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc TileX}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="TileXSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc TileX}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="TileXSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc TileY}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="TileYSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc TileY}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="TileYSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Gas}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GasOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Gas}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GasOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Amount}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="AmountSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Amount}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="AmountSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <Button Name="SubmitButton" Text="{Loc Add Gas}" />
     </VBoxContainer>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml
index 7552c40e61..c693a4be4b 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml
@@ -1,12 +1,10 @@
-<MarginContainer
+<Control
     xmlns="https://spacestation14.io"
     xmlns:amc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:at="clr-namespace:Content.Client.UserInterface.AdminMenu.Tabs.AtmosTab"
-    MarginLeftOverride="4"
-    MarginTopOverride="4" MarginRightOverride="4"
-    MarginBottomOverride="4"
-    CustomMinimumSize="50 50">
+    Margin="4"
+    MinSize="50 50">
     <GridContainer Columns="4">
         <amc:UICommandButton Text="{Loc Add Atmos}" Command="addatmos" WindowType="{x:Type at:AddAtmosWindow}" />
         <amc:UICommandButton Text="{Loc Add Gas}" Command="addgas" WindowType="{x:Type at:AddGasWindow}" />
@@ -14,4 +12,4 @@
         <amc:UICommandButton Text="{Loc Set Temperature}" Command="settemp"
                              WindowType="{x:Type at:SetTemperatureWindow}" />
     </GridContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml.cs
index fe66f29400..4a81056e9c 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/AtmosTab.xaml.cs
@@ -1,11 +1,12 @@
 #nullable enable
 using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 
 namespace Content.Client.UserInterface.AdminMenu.Tabs.AtmosTab
 {
     [GenerateTypedNameReferences]
-    public partial class AtmosTab : MarginContainer
+    public partial class AtmosTab : Control
     {
     }
 }
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/FillGasWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/FillGasWindow.xaml
index 9602c8607b..e06e390ba8 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/FillGasWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/FillGasWindow.xaml
@@ -2,19 +2,19 @@
     xmlns="https://spacestation14.io" Title="{Loc Fill Gas}">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Grid}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GridOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Grid}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GridOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Gas}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GasOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Gas}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GasOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Amount}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="AmountSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Amount}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="AmountSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <Button Name="SubmitButton" Text="{Loc Fill Gas}" />
     </VBoxContainer>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/SetTemperatureWindow.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/SetTemperatureWindow.xaml
index 49f45b3158..97abb3ecb7 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/SetTemperatureWindow.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/AtmosTab/SetTemperatureWindow.xaml
@@ -2,24 +2,24 @@
     xmlns="https://spacestation14.io" Title="{Loc Set Temperature}">
     <VBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Grid}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <OptionButton Name="GridOptions" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Grid}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <OptionButton Name="GridOptions" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc TileX}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="TileXSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc TileX}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="TileXSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc TileY}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="TileYSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc TileY}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="TileYSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <HBoxContainer>
-            <Label Text="{Loc Temperature}" CustomMinimumSize="100 0" />
-            <Control CustomMinimumSize="50 0" />
-            <SpinBox Name="TemperatureSpin" CustomMinimumSize="100 0" SizeFlagsHorizontal="FillExpand" />
+            <Label Text="{Loc Temperature}" MinSize="100 0" />
+            <Control MinSize="50 0" />
+            <SpinBox Name="TemperatureSpin" MinSize="100 0" HorizontalExpand="True" />
         </HBoxContainer>
         <Button Name="SubmitButton" Text="{Loc Set Temperature}" />
     </VBoxContainer>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml
index 0cfeb99467..4cca89fb11 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml
@@ -1,15 +1,14 @@
-<MarginContainer
-    xmlns="https://spacestation14.io">
-    <VBoxContainer SizeFlagsVertical="Fill">
-        <HBoxContainer SizeFlagsVertical="Fill">
-            <Label Name="PlayerCount" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.7"
+<Control xmlns="https://spacestation14.io">
+    <VBoxContainer>
+        <HBoxContainer>
+            <Label Name="PlayerCount" HorizontalExpand="True" SizeFlagsStretchRatio="0.7"
                    Text="{Loc Player Count}" />
-            <Button Name="RefreshButton" SizeFlagsHorizontal="FillExpand" SizeFlagsStretchRatio="0.3"
+            <Button Name="RefreshButton" HorizontalExpand="True" SizeFlagsStretchRatio="0.3"
                     Text="{Loc Refresh}" />
         </HBoxContainer>
-        <Control CustomMinimumSize="0 5" />
-        <ScrollContainer SizeFlagsHorizontal="FillExpand" SizeFlagsVertical="FillExpand">
+        <Control MinSize="0 5" />
+        <ScrollContainer HorizontalExpand="True" VerticalExpand="True">
             <VBoxContainer Name="PlayerList" />
         </ScrollContainer>
     </VBoxContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml.cs
index 03f0eaffb5..df08b3e883 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/PlayerTab.xaml.cs
@@ -13,7 +13,7 @@ using Robust.Shared.Maths;
 namespace Content.Client.UserInterface.AdminMenu.Tabs
 {
     [GenerateTypedNameReferences]
-    public partial class PlayerTab : MarginContainer
+    public partial class PlayerTab : Control
     {
         public delegate void PlayerListRefresh();
 
@@ -42,7 +42,7 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
 
             var header = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SeparationOverride = 4,
                 Children =
                 {
@@ -50,14 +50,14 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
                     {
                         Text = "Name",
                         SizeFlagsStretchRatio = 2f,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     },
                     new VSeparator(),
                     new Label
                     {
                         Text = "Player",
                         SizeFlagsStretchRatio = 2f,
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     }
                 }
             };
@@ -79,7 +79,7 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
             {
                 var hBox = new HBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     SeparationOverride = 4,
                     Children =
                     {
@@ -87,7 +87,7 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
                         {
                             Text = name,
                             SizeFlagsStretchRatio = 2f,
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             ClipText = true
                         },
                         new VSeparator(),
@@ -95,7 +95,7 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
                         {
                             Text = player,
                             SizeFlagsStretchRatio = 2f,
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
                             ClipText = true
                         }
                     }
@@ -121,7 +121,7 @@ namespace Content.Client.UserInterface.AdminMenu.Tabs
         {
             public VSeparator()
             {
-                CustomMinimumSize = (2, 5);
+                MinSize = (2, 5);
                 AddChild(new PanelContainer
                 {
                     PanelOverride = new StyleBoxFlat
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml
index 68c1c065a6..0eef4d4bee 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml
@@ -1,14 +1,12 @@
-<MarginContainer
+<Control
     xmlns="https://spacestation14.io"
     xmlns:amc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
-    MarginLeftOverride="4"
-    MarginTopOverride="4" MarginRightOverride="4"
-    MarginBottomOverride="4"
-    CustomMinimumSize="50 50">
+    Margin="4"
+    MinSize="50 50">
     <GridContainer
         Columns="4">
         <amc:CommandButton Command="startround" Text="{Loc Start Round}" />
         <amc:CommandButton Command="endround" Text="{Loc End Round}" />
         <amc:CommandButton Command="restartround" Text="{Loc Restart Round}" />
     </GridContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml.cs
index 388e92905c..cc47b33c65 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/RoundTab.xaml.cs
@@ -1,11 +1,12 @@
 #nullable enable
 using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 
 namespace Content.Client.UserInterface.AdminMenu.Tabs
 {
     [GenerateTypedNameReferences]
-    public partial class RoundTab : MarginContainer
+    public partial class RoundTab : Control
     {
     }
 }
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml b/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml
index 5f7f94a227..36847af899 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml
@@ -1,13 +1,11 @@
-<MarginContainer
+<Control
     xmlns="https://spacestation14.io"
     xmlns:amc="clr-namespace:Content.Client.UserInterface.AdminMenu.CustomControls"
-    MarginLeftOverride="4"
-    MarginTopOverride="4" MarginRightOverride="4"
-    MarginBottomOverride="4"
-    CustomMinimumSize="50 50">
+    Margin="4"
+    MinSize="50 50">
     <GridContainer
         Columns="4" >
         <amc:CommandButton Command="restart" Text="{Loc Reboot}"></amc:CommandButton>
         <amc:CommandButton Command="shutdown" Text="{Loc Shutdown}"></amc:CommandButton>
     </GridContainer>
-</MarginContainer>
+</Control>
diff --git a/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml.cs b/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml.cs
index cb2fd372da..9e2a3be0e3 100644
--- a/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml.cs
+++ b/Content.Client/UserInterface/AdminMenu/Tabs/ServerTab.xaml.cs
@@ -1,14 +1,12 @@
 #nullable enable
 using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 
 namespace Content.Client.UserInterface.AdminMenu.Tabs
 {
     [GenerateTypedNameReferences]
-    public partial class ServerTab : MarginContainer
+    public partial class ServerTab : Control
     {
-        public ServerTab()
-        {
-        }
     }
 }
diff --git a/Content.Client/UserInterface/AlertsUI.cs b/Content.Client/UserInterface/AlertsUI.cs
index 04c7ad44fd..30409963a4 100644
--- a/Content.Client/UserInterface/AlertsUI.cs
+++ b/Content.Client/UserInterface/AlertsUI.cs
@@ -1,7 +1,6 @@
 using Content.Client.UserInterface.Stylesheets;
 using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
-using Robust.Shared.Maths;
 
 namespace Content.Client.UserInterface
 {
@@ -25,37 +24,35 @@ namespace Content.Client.UserInterface
             var panelContainer = new PanelContainer
             {
                 StyleClasses = {StyleNano.StyleClassTransparentBorderedWindowPanel},
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
-                SizeFlagsVertical = SizeFlags.None
+                HorizontalAlignment = HAlignment.Right,
+                VerticalAlignment = VAlignment.Top
             };
             AddChild(panelContainer);
 
             Grid = new GridContainer
             {
-                MaxHeight = 64,
+                MaxGridHeight = 64,
                 ExpandBackwards = true
             };
             panelContainer.AddChild(Grid);
+
+            MinSize = (64, 64);
         }
 
+        // This makes no sense but I'm leaving it in place in case I break anything by removing it.
+
         protected override void Resized()
         {
             // TODO: Can rework this once https://github.com/space-wizards/RobustToolbox/issues/1392 is done,
             // this is here because there isn't currently a good way to allow the grid to adjust its height based
             // on constraints, otherwise we would use anchors to lay it out
             base.Resized();
-            Grid.MaxHeight = Height;
-        }
-
-        protected override Vector2 CalculateMinimumSize()
-        {
-            // allows us to shrink down to a single row
-            return (64, 64);
+            Grid.MaxGridHeight = Height;
         }
 
         protected override void UIScaleChanged()
         {
-            Grid.MaxHeight = Height;
+            Grid.MaxGridHeight = Height;
             base.UIScaleChanged();
         }
     }
diff --git a/Content.Client/UserInterface/Atmos/GasTank/GasTankWindow.cs b/Content.Client/UserInterface/Atmos/GasTank/GasTankWindow.cs
index 9135c08391..a43adb2dc4 100644
--- a/Content.Client/UserInterface/Atmos/GasTank/GasTankWindow.cs
+++ b/Content.Client/UserInterface/Atmos/GasTank/GasTankWindow.cs
@@ -72,7 +72,7 @@ namespace Content.Client.UserInterface.Atmos.GasTank
                 Children =
                 {
                     (_topContainer = new VBoxContainer()),
-                    new Control {CustomMinimumSize = (0, 110)}
+                    new Control {MinSize = (0, 110)}
                 }
             };
 
@@ -82,37 +82,26 @@ namespace Content.Client.UserInterface.Atmos.GasTank
 
             var font = _resourceCache.GetFont("/Fonts/Boxfont-round/Boxfont Round.ttf", 13);
 
-            var topRow = new MarginContainer
+            var topRow = new HBoxContainer
             {
-                MarginLeftOverride = 4,
-                MarginTopOverride = 2,
-                MarginRightOverride = 12,
-                MarginBottomOverride = 2,
+                Margin = new Thickness(4, 2, 12, 2),
                 Children =
                 {
-                    new HBoxContainer
+                    (_lblName = new Label
                     {
-                        Children =
-                        {
-                            (_lblName = new Label
-                            {
-                                Text = Loc.GetString("Gas Tank"),
-                                FontOverride = font,
-                                FontColorOverride = StyleNano.NanoGold,
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            }),
-                            new Control
-                            {
-                                CustomMinimumSize = (20, 0),
-                                SizeFlagsHorizontal = SizeFlags.Expand
-                            },
-                            (btnClose = new TextureButton
-                            {
-                                StyleClasses = {SS14Window.StyleClassWindowCloseButton},
-                                SizeFlagsVertical = SizeFlags.ShrinkCenter
-                            })
-                        }
-                    }
+                        Text = Loc.GetString("Gas Tank"),
+                        FontOverride = font,
+                        FontColorOverride = StyleNano.NanoGold,
+                        VerticalAlignment = VAlignment.Center,
+                        HorizontalExpand = true,
+                        HorizontalAlignment = HAlignment.Left,
+                        Margin = new Thickness(0, 0, 20, 0),
+                    }),
+                    (btnClose = new TextureButton
+                    {
+                        StyleClasses = {SS14Window.StyleClassWindowCloseButton},
+                        VerticalAlignment = VAlignment.Center
+                    })
                 }
             };
 
@@ -121,30 +110,23 @@ namespace Content.Client.UserInterface.Atmos.GasTank
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#202025")},
                 Children =
                 {
-                    new MarginContainer
+                    (_contentContainer = new VBoxContainer
                     {
-                        MarginLeftOverride = 8,
-                        MarginRightOverride = 8,
-                        MarginTopOverride = 4,
-                        MarginBottomOverride = 4,
-                        Children =
-                        {
-                            (_contentContainer = new VBoxContainer())
-                        }
-                    }
+                        Margin = new Thickness(8, 4),
+                    })
                 }
             };
 
             _topContainer.AddChild(topRow);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
+                MinSize = (0, 2),
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
             _topContainer.AddChild(middle);
             _topContainer.AddChild(new PanelContainer
             {
-                CustomMinimumSize = (0, 2),
+                MinSize = (0, 2),
                 PanelOverride = new StyleBoxFlat {BackgroundColor = Color.FromHex("#525252ff")}
             });
 
@@ -154,26 +136,20 @@ namespace Content.Client.UserInterface.Atmos.GasTank
 
             //internals
             _lblInternals = new RichTextLabel
-                {CustomMinimumSize = (200, 0), SizeFlagsVertical = SizeFlags.ShrinkCenter};
+                {MinSize = (200, 0), VerticalAlignment = VAlignment.Center};
             _btnInternals = new Button {Text = Loc.GetString("Toggle")};
 
             _contentContainer.AddChild(
-                new MarginContainer
+                new HBoxContainer
                 {
-                    MarginTopOverride = 7,
-                    Children =
-                    {
-                        new HBoxContainer
-                        {
-                            Children = {_lblInternals, _btnInternals}
-                        }
-                    }
+                    Margin = new Thickness(0, 7, 0, 0),
+                    Children = {_lblInternals, _btnInternals}
                 });
 
             // Separator
             _contentContainer.AddChild(new Control
             {
-                CustomMinimumSize = new Vector2(0, 10)
+                MinSize = new Vector2(0, 10)
             });
 
             _contentContainer.AddChild(new Label
@@ -181,19 +157,12 @@ namespace Content.Client.UserInterface.Atmos.GasTank
                 Text = Loc.GetString("Output Pressure"),
                 Align = Label.AlignMode.Center
             });
-            _spbPressure = new FloatSpinBox {IsValid = f => f >= 0 || f <= 3000};
-            _contentContainer.AddChild(
-                new MarginContainer
-                {
-                    MarginRightOverride = 25,
-                    MarginLeftOverride = 25,
-                    MarginBottomOverride = 7,
-                    Children =
-                    {
-                        _spbPressure
-                    }
-                }
-            );
+            _spbPressure = new FloatSpinBox
+            {
+                IsValid = f => f >= 0 || f <= 3000,
+                Margin = new Thickness(25, 0, 25, 7)
+            };
+            _contentContainer.AddChild(_spbPressure);
 
             // Handlers
             _spbPressure.OnValueChanged += args =>
diff --git a/Content.Client/UserInterface/Cargo/CargoConsoleMenu.cs b/Content.Client/UserInterface/Cargo/CargoConsoleMenu.cs
index 5103fa58c1..acd34ab97b 100644
--- a/Content.Client/UserInterface/Cargo/CargoConsoleMenu.cs
+++ b/Content.Client/UserInterface/Cargo/CargoConsoleMenu.cs
@@ -15,8 +15,6 @@ namespace Content.Client.UserInterface.Cargo
 {
     public class CargoConsoleMenu : SS14Window
     {
-        protected override Vector2? CustomSize => (400, 600);
-
         public CargoConsoleBoundUserInterface Owner { get; private set; }
 
         public event Action<BaseButton.ButtonEventArgs> OnItemSelected;
@@ -42,6 +40,7 @@ namespace Content.Client.UserInterface.Cargo
 
         public CargoConsoleMenu(CargoConsoleBoundUserInterface owner)
         {
+            SetSize = MinSize = (400, 600);
             IoCManager.InjectDependencies(this);
             Owner = owner;
 
@@ -112,7 +111,7 @@ namespace Content.Client.UserInterface.Cargo
                 //Text = Loc.GetString("Call Shuttle"),
                 Text = Loc.GetString("Activate Telepad"), //Shuttle code pending
                 TextAlign = Label.AlignMode.Center,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
             PermissionsButton = new Button()
             {
@@ -127,13 +126,13 @@ namespace Content.Client.UserInterface.Cargo
             _categories = new OptionButton
             {
                 Prefix = Loc.GetString("Categories: "),
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 1
             };
             _searchBar = new LineEdit
             {
                 PlaceHolder = Loc.GetString("Search"),
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 1
             };
             category.AddChild(_categories);
@@ -142,41 +141,41 @@ namespace Content.Client.UserInterface.Cargo
 
             var products = new ScrollContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 6
             };
             Products = new VBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand
+                HorizontalExpand = true,
+                VerticalExpand = true
             };
             products.AddChild(Products);
             rows.AddChild(products);
 
             var requestsAndOrders = new PanelContainer
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 6,
                 PanelOverride = new StyleBoxFlat { BackgroundColor = Color.Black }
             };
             var orderScrollBox = new ScrollContainer
             {
-                SizeFlagsVertical = SizeFlags.FillExpand
+                VerticalExpand = true
             };
             var rAndOVBox = new VBoxContainer();
             var requestsLabel = new Label { Text = Loc.GetString("Requests") };
             _requests = new VBoxContainer // replace with scroll box so that approval buttons can be added
             {
                 StyleClasses = { "transparentItemList" },
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1,
             };
             var ordersLabel = new Label { Text = Loc.GetString("Orders") };
             _orders = new VBoxContainer
             {
                 StyleClasses = { "transparentItemList" },
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1,
             };
             rAndOVBox.AddChild(requestsLabel);
@@ -189,7 +188,7 @@ namespace Content.Client.UserInterface.Cargo
 
             rows.AddChild(new TextureButton
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
             });
             Contents.AddChild(rows);
 
@@ -351,30 +350,30 @@ namespace Content.Client.UserInterface.Cargo
 
         public CargoProductRow()
         {
-            SizeFlagsHorizontal = SizeFlags.FillExpand;
+            HorizontalExpand = true;
 
             MainButton = new Button
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand
+                HorizontalExpand = true,
+                VerticalExpand = true
             };
             AddChild(MainButton);
 
             var hBox = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
 
             Icon = new TextureRect
             {
-                CustomMinimumSize = new Vector2(32.0f, 32.0f),
+                MinSize = new Vector2(32.0f, 32.0f),
                 RectClipContent = true
             };
             hBox.AddChild(Icon);
 
             ProductName = new Label
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             };
             hBox.AddChild(ProductName);
 
@@ -384,7 +383,7 @@ namespace Content.Client.UserInterface.Cargo
             };
             PointCost = new Label
             {
-                CustomMinimumSize = new Vector2(40.0f, 32.0f),
+                MinSize = new Vector2(40.0f, 32.0f),
                 Align = Label.AlignMode.Right
             };
             panel.AddChild(PointCost);
@@ -405,34 +404,34 @@ namespace Content.Client.UserInterface.Cargo
 
         public CargoOrderRow()
         {
-            SizeFlagsHorizontal = SizeFlags.FillExpand;
+            HorizontalExpand = true;
 
             var hBox = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
             };
 
             Icon = new TextureRect
             {
-                CustomMinimumSize = new Vector2(32.0f, 32.0f),
+                MinSize = new Vector2(32.0f, 32.0f),
                 RectClipContent = true
             };
             hBox.AddChild(Icon);
 
             var vBox = new VBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand
+                HorizontalExpand = true,
+                VerticalExpand = true
             };
             ProductName = new Label
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 StyleClasses = { StyleNano.StyleClassLabelSubText },
                 ClipText = true
             };
             Description = new Label
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 StyleClasses = { StyleNano.StyleClassLabelSubText },
                 ClipText = true
             };
diff --git a/Content.Client/UserInterface/Cargo/CargoConsoleOrderMenu.cs b/Content.Client/UserInterface/Cargo/CargoConsoleOrderMenu.cs
index bbb6e65bcc..9f41848133 100644
--- a/Content.Client/UserInterface/Cargo/CargoConsoleOrderMenu.cs
+++ b/Content.Client/UserInterface/Cargo/CargoConsoleOrderMenu.cs
@@ -35,7 +35,7 @@ namespace Content.Client.UserInterface.Cargo
             var amountLabel = new Label { Text = Loc.GetString("Amount:") };
             Amount = new SpinBox
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 Value = 1
             };
             Amount.SetButtons(new List<int>() { -100, -10, -1 }, new List<int>() { 1, 10, 100 });
diff --git a/Content.Client/UserInterface/Cargo/GalacticBankSelectionMenu.cs b/Content.Client/UserInterface/Cargo/GalacticBankSelectionMenu.cs
index be6a5035e1..e4179617f2 100644
--- a/Content.Client/UserInterface/Cargo/GalacticBankSelectionMenu.cs
+++ b/Content.Client/UserInterface/Cargo/GalacticBankSelectionMenu.cs
@@ -16,27 +16,18 @@ namespace Content.Client.UserInterface.Cargo
         private int[] _accountIds = new int[] { };
         private int _selectedAccountId = -1;
 
-        protected override Vector2? CustomSize => (300, 300);
-
         public CargoConsoleBoundUserInterface Owner;
 
         public GalacticBankSelectionMenu()
         {
+            MinSize = SetSize = (300, 300);
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("Galactic Bank Selection");
 
             _accounts = new ItemList() { SelectMode = ItemList.ItemListSelectMode.Single };
 
-            var margin = new MarginContainer()
-            {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-            };
-
-            margin.AddChild(_accounts);
-
-            Contents.AddChild(margin);
+            Contents.AddChild(_accounts);
         }
 
         public void Populate(int accountCount, string[] accountNames, int[] accountIds, int selectedAccountId)
diff --git a/Content.Client/UserInterface/CharacterSetupGui.cs b/Content.Client/UserInterface/CharacterSetupGui.cs
index b9d2ea1824..f7eebf0044 100644
--- a/Content.Client/UserInterface/CharacterSetupGui.cs
+++ b/Content.Client/UserInterface/CharacterSetupGui.cs
@@ -36,12 +36,9 @@ namespace Content.Client.UserInterface
         {
             _entityManager = entityManager;
             _preferencesManager = preferencesManager;
-            var margin = new MarginContainer
+            var margin = new Control
             {
-                MarginBottomOverride = 20,
-                MarginLeftOverride = 20,
-                MarginRightOverride = 20,
-                MarginTopOverride = 20
+                Margin = new Thickness(20),
             };
 
             AddChild(margin);
@@ -67,32 +64,25 @@ namespace Content.Client.UserInterface
 
             var topHBox = new HBoxContainer
             {
-                CustomMinimumSize = (0, 40),
+                MinSize = (0, 40),
                 Children =
                 {
-                    new MarginContainer
+                    new Label
                     {
-                        MarginLeftOverride = 8,
-                        Children =
-                        {
-                            new Label
-                            {
-                                Text = Loc.GetString("Character Setup"),
-                                StyleClasses = {StyleNano.StyleClassLabelHeadingBigger},
-                                VAlign = Label.VAlignMode.Center,
-                                SizeFlagsHorizontal = SizeFlags.Expand | SizeFlags.ShrinkCenter
-                            }
-                        }
+                        Margin = new Thickness(8, 0, 0, 0),
+                        Text = Loc.GetString("Character Setup"),
+                        StyleClasses = {StyleNano.StyleClassLabelHeadingBigger},
+                        VAlign = Label.VAlignMode.Center,
                     },
                     (SaveButton = new Button
                     {
-                        SizeFlagsHorizontal = SizeFlags.Expand | SizeFlags.ShrinkEnd,
+                        HorizontalExpand = true,
+                        HorizontalAlignment = HAlignment.Right,
                         Text = Loc.GetString("Save"),
                         StyleClasses = {StyleNano.StyleClassButtonBig},
                     }),
                     (CloseButton = new Button
                     {
-                        SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
                         Text = Loc.GetString("Close"),
                         StyleClasses = {StyleNano.StyleClassButtonBig},
                     })
@@ -112,29 +102,20 @@ namespace Content.Client.UserInterface
 
             var hBox = new HBoxContainer
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SeparationOverride = 0
             };
             vBox.AddChild(hBox);
 
             _charactersVBox = new VBoxContainer();
 
-            hBox.AddChild(new MarginContainer
+            hBox.AddChild(new ScrollContainer
             {
-                CustomMinimumSize = (330, 0),
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                MarginTopOverride = 5,
-                MarginLeftOverride = 5,
+                MinSize = (325, 0),
+                Margin = new Thickness(5, 5, 0, 0),
                 Children =
                 {
-                    new ScrollContainer
-                    {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
-                        Children =
-                        {
-                            _charactersVBox
-                        }
-                    }
+                    _charactersVBox
                 }
             });
 
@@ -152,7 +133,7 @@ namespace Content.Client.UserInterface
             hBox.AddChild(new PanelContainer
             {
                 PanelOverride = new StyleBoxFlat {BackgroundColor = StyleNano.NanoGold},
-                CustomMinimumSize = (2, 0)
+                MinSize = (2, 0)
             });
             _humanoidProfileEditor = new HumanoidProfileEditor(preferencesManager, prototypeManager, entityManager);
             _humanoidProfileEditor.OnProfileChanged += newProfile => { UpdateUI(); };
@@ -266,7 +247,7 @@ namespace Content.Client.UserInterface
                 {
                     Text = description,
                     ClipText = true,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand
+                    HorizontalExpand = true
                 };
                 var deleteButton = new Button
                 {
@@ -281,7 +262,7 @@ namespace Content.Client.UserInterface
 
                 var internalHBox = new HBoxContainer
                 {
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                    HorizontalExpand = true,
                     SeparationOverride = 0,
                     Children =
                     {
diff --git a/Content.Client/UserInterface/Controls/ActionSlot.cs b/Content.Client/UserInterface/Controls/ActionSlot.cs
index aa9cf73b9d..d9d941ade9 100644
--- a/Content.Client/UserInterface/Controls/ActionSlot.cs
+++ b/Content.Client/UserInterface/Controls/ActionSlot.cs
@@ -131,8 +131,8 @@ namespace Content.Client.UserInterface.Controls
             SlotIndex = slotIndex;
             MouseFilter = MouseFilterMode.Stop;
 
-            CustomMinimumSize = (64, 64);
-            SizeFlagsVertical = SizeFlags.None;
+            MinSize = (64, 64);
+            VerticalAlignment = VAlignment.Top;
             TooltipDelay = CustomTooltipDelay;
             TooltipSupplier = SupplyTooltip;
 
@@ -144,29 +144,29 @@ namespace Content.Client.UserInterface.Controls
 
             _bigActionIcon = new TextureRect
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 Stretch = TextureRect.StretchMode.Scale,
                 Visible = false
             };
             _bigItemSpriteView = new SpriteView
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                HorizontalExpand = true,
+                VerticalExpand = true,
                 Scale = (2,2),
                 Visible = false
             };
             _smallActionIcon = new TextureRect
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
-                SizeFlagsVertical = SizeFlags.ShrinkEnd,
+                HorizontalAlignment = HAlignment.Right,
+                VerticalAlignment = VAlignment.Bottom,
                 Stretch = TextureRect.StretchMode.Scale,
                 Visible = false
             };
             _smallItemSpriteView = new SpriteView
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
-                SizeFlagsVertical = SizeFlags.ShrinkEnd,
+                HorizontalAlignment = HAlignment.Right,
+                VerticalAlignment = VAlignment.Bottom,
                 Visible = false
             };
 
@@ -175,28 +175,26 @@ namespace Content.Client.UserInterface.Controls
             // padding to the left of the number to shift it right
             var paddingBox = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                CustomMinimumSize = (64, 64)
+                HorizontalExpand = true,
+                VerticalExpand = true,
+                MinSize = (64, 64)
             };
             paddingBox.AddChild(new Control()
             {
-                CustomMinimumSize = (4, 4),
-                SizeFlagsVertical = SizeFlags.Fill
+                MinSize = (4, 4),
             });
             paddingBox.AddChild(_number);
 
             // padding to the left of the small icon
             var paddingBoxItemIcon = new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                CustomMinimumSize = (64, 64)
+                HorizontalExpand = true,
+                VerticalExpand = true,
+                MinSize = (64, 64)
             };
             paddingBoxItemIcon.AddChild(new Control()
             {
-                CustomMinimumSize = (32, 32),
-                SizeFlagsVertical = SizeFlags.Fill
+                MinSize = (32, 32),
             });
             paddingBoxItemIcon.AddChild(new Control
             {
diff --git a/Content.Client/UserInterface/CreditsWindow.cs b/Content.Client/UserInterface/CreditsWindow.cs
index ca718223a8..af4624b6ab 100644
--- a/Content.Client/UserInterface/CreditsWindow.cs
+++ b/Content.Client/UserInterface/CreditsWindow.cs
@@ -38,9 +38,18 @@ namespace Content.Client.UserInterface
 
             var rootContainer = new TabContainer();
 
-            var patronsList = new ScrollContainer();
-            var ss14ContributorsList = new ScrollContainer();
-            var licensesList = new ScrollContainer();
+            var patronsList = new ScrollContainer
+            {
+                HScrollEnabled = false
+            };
+            var ss14ContributorsList = new ScrollContainer
+            {
+                HScrollEnabled = false
+            };
+            var licensesList = new ScrollContainer
+            {
+                HScrollEnabled = false
+            };
 
             rootContainer.AddChild(ss14ContributorsList);
             rootContainer.AddChild(patronsList);
@@ -56,14 +65,15 @@ namespace Content.Client.UserInterface
 
             Contents.AddChild(rootContainer);
 
-            CustomMinimumSize = (650, 450);
+            SetSize = (650, 650);
         }
 
         private void PopulateLicenses(ScrollContainer licensesList)
         {
-            var margin = new MarginContainer {MarginLeftOverride = 2, MarginTopOverride = 2};
-            var vBox = new VBoxContainer();
-            margin.AddChild(vBox);
+            var vBox = new VBoxContainer
+            {
+                Margin = new Thickness(2, 2, 0, 0)
+            };
 
             foreach (var entry in CreditsManager.GetLicenses().OrderBy(p => p.Name))
             {
@@ -77,14 +87,15 @@ namespace Content.Client.UserInterface
                 }
             }
 
-            licensesList.AddChild(margin);
+            licensesList.AddChild(vBox);
         }
 
         private void PopulatePatronsList(Control patronsList)
         {
-            var margin = new MarginContainer {MarginLeftOverride = 2, MarginTopOverride = 2};
-            var vBox = new VBoxContainer();
-            margin.AddChild(vBox);
+            var vBox = new VBoxContainer
+            {
+                Margin = new Thickness(2, 2, 0, 0)
+            };
             var patrons = LoadPatrons();
 
             // Do not show "become a patron" button on Steam builds
@@ -95,7 +106,7 @@ namespace Content.Client.UserInterface
                 vBox.AddChild(patronButton = new Button
                 {
                     Text = "Become a Patron",
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center
                 });
 
                 patronButton.OnPressed +=
@@ -107,7 +118,7 @@ namespace Content.Client.UserInterface
             {
                 if (!first)
                 {
-                    vBox.AddChild(new Control {CustomMinimumSize = (0, 10)});
+                    vBox.AddChild(new Control {MinSize = (0, 10)});
                 }
 
                 first = false;
@@ -123,7 +134,7 @@ namespace Content.Client.UserInterface
 
 
 
-            patronsList.AddChild(margin);
+            patronsList.AddChild(vBox);
         }
 
         private IEnumerable<PatronEntry> LoadPatrons()
@@ -140,17 +151,14 @@ namespace Content.Client.UserInterface
         {
             Button contributeButton;
 
-            var margin = new MarginContainer
+            var vBox = new VBoxContainer
             {
-                MarginLeftOverride = 2,
-                MarginTopOverride = 2
+                Margin = new Thickness(2, 2, 0, 0)
             };
-            var vBox = new VBoxContainer();
-            margin.AddChild(vBox);
 
             vBox.AddChild(new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
                 SeparationOverride = 20,
                 Children =
                 {
@@ -165,7 +173,7 @@ namespace Content.Client.UserInterface
             {
                 if (!first)
                 {
-                    vBox.AddChild(new Control {CustomMinimumSize = (0, 10)});
+                    vBox.AddChild(new Control {MinSize = (0, 10)});
                 }
 
                 first = false;
@@ -190,7 +198,7 @@ namespace Content.Client.UserInterface
             AddSection("Original Space Station 13 Remake Team", "OriginalRemake.txt");
             AddSection("Special Thanks", "SpecialThanks.txt", true);
 
-            contributorsList.AddChild(margin);
+            contributorsList.AddChild(vBox);
 
             contributeButton.OnPressed += _ =>
                 IoCManager.Resolve<IUriOpener>().OpenUri(UILinks.GitHub);
diff --git a/Content.Client/UserInterface/GameHud.cs b/Content.Client/UserInterface/GameHud.cs
index bc1b580139..7d68a7b996 100644
--- a/Content.Client/UserInterface/GameHud.cs
+++ b/Content.Client/UserInterface/GameHud.cs
@@ -132,7 +132,7 @@ namespace Content.Client.UserInterface
 
         public void Initialize()
         {
-            RootControl = new LC();
+            RootControl = new LC { Name = "AAAAAAAAAAAAAAAAAAAAAA"};
             LC.SetAnchorPreset(RootControl, LC.LayoutPreset.Wide);
 
             var escapeTexture = _resourceCache.GetTexture("/Textures/Interface/hamburger.svg.192dpi.png");
@@ -162,7 +162,7 @@ namespace Content.Client.UserInterface
             _buttonEscapeMenu = new TopButton(escapeTexture, EngineKeyFunctions.EscapeMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open escape menu."),
-                CustomMinimumSize = (70, 64),
+                MinSize = (70, 64),
                 StyleClasses = {StyleBase.ButtonOpenRight}
             };
 
@@ -174,7 +174,7 @@ namespace Content.Client.UserInterface
             _buttonCharacterMenu = new TopButton(characterTexture, ContentKeyFunctions.OpenCharacterMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open character menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -187,7 +187,7 @@ namespace Content.Client.UserInterface
             _buttonInventoryMenu = new TopButton(inventoryTexture, ContentKeyFunctions.OpenInventoryMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open inventory menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -200,7 +200,7 @@ namespace Content.Client.UserInterface
             _buttonCraftingMenu = new TopButton(craftingTexture, ContentKeyFunctions.OpenCraftingMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open crafting menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -213,7 +213,7 @@ namespace Content.Client.UserInterface
             _buttonActionsMenu = new TopButton(actionsTexture, ContentKeyFunctions.OpenActionsMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open actions menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -226,7 +226,7 @@ namespace Content.Client.UserInterface
             _buttonAdminMenu = new TopButton(adminTexture, ContentKeyFunctions.OpenAdminMenu, _inputManager)
             {
                 ToolTip = Loc.GetString("Open admin menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -239,7 +239,7 @@ namespace Content.Client.UserInterface
             _buttonSandboxMenu = new TopButton(sandboxTexture, ContentKeyFunctions.OpenSandboxWindow, _inputManager)
             {
                 ToolTip = Loc.GetString("Open sandbox menu."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 Visible = false,
                 StyleClasses = {StyleBase.ButtonSquare}
             };
@@ -252,7 +252,7 @@ namespace Content.Client.UserInterface
             _buttonTutorial = new TopButton(tutorialTexture, ContentKeyFunctions.OpenTutorial, _inputManager)
             {
                 ToolTip = Loc.GetString("Open tutorial."),
-                CustomMinimumSize = topMinSize,
+                MinSize = topMinSize,
                 StyleClasses = {StyleBase.ButtonOpenLeft, TopButton.StyleClassRedTopButton},
             };
 
@@ -300,25 +300,25 @@ namespace Content.Client.UserInterface
             LC.SetMarginBottom(centerBottomContainer, -10f);
             RootControl.AddChild(centerBottomContainer);
 
-            HandsContainer = new MarginContainer
+            HandsContainer = new Control
             {
-                SizeFlagsVertical = Control.SizeFlags.ShrinkEnd
+                VerticalAlignment = Control.VAlignment.Bottom,
             };
-            RightInventoryQuickButtonContainer = new MarginContainer
+            RightInventoryQuickButtonContainer = new Control
             {
-                SizeFlagsVertical = Control.SizeFlags.ShrinkEnd
+                VerticalAlignment = Control.VAlignment.Bottom,
             };
-            LeftInventoryQuickButtonContainer = new MarginContainer
+            LeftInventoryQuickButtonContainer = new Control
             {
-                SizeFlagsVertical = Control.SizeFlags.ShrinkEnd
+                VerticalAlignment = Control.VAlignment.Bottom,
             };
             centerBottomContainer.AddChild(LeftInventoryQuickButtonContainer);
             centerBottomContainer.AddChild(HandsContainer);
             centerBottomContainer.AddChild(RightInventoryQuickButtonContainer);
 
-            SuspicionContainer = new MarginContainer
+            SuspicionContainer = new Control
             {
-                SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter
+                HorizontalAlignment = Control.HAlignment.Center
             };
 
             RootControl.AddChild(SuspicionContainer);
@@ -330,7 +330,7 @@ namespace Content.Client.UserInterface
 
             _topNotificationContainer = new VBoxContainer
             {
-                CustomMinimumSize = (600, 0)
+                MinSize = (600, 0)
             };
             RootControl.AddChild(_topNotificationContainer);
             LC.SetAnchorPreset(_topNotificationContainer, LC.LayoutPreset.CenterTop);
@@ -498,21 +498,21 @@ namespace Content.Client.UserInterface
                     {
                         Children =
                         {
-                            new Control {CustomMinimumSize = (0, VertPad)},
                             (_textureRect = new TextureRect
                             {
                                 TextureScale = (0.5f, 0.5f),
                                 Texture = texture,
-                                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                                SizeFlagsVertical = SizeFlags.Expand | SizeFlags.ShrinkCenter,
+                                HorizontalAlignment = HAlignment.Center,
+                                VerticalAlignment = VAlignment.Center,
+                                VerticalExpand = true,
+                                Margin = new Thickness(0, VertPad),
                                 ModulateSelfOverride = NormalColor,
                                 Stretch = TextureRect.StretchMode.KeepCentered
                             }),
-                            new Control {CustomMinimumSize = (0, VertPad)},
                             (_label = new Label
                             {
                                 Text = ShortKeyName(_function),
-                                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
+                                HorizontalAlignment = HAlignment.Center,
                                 ModulateSelfOverride = NormalColor,
                                 StyleClasses = {StyleClassLabelTopButton}
                             })
diff --git a/Content.Client/UserInterface/GhostGui.cs b/Content.Client/UserInterface/GhostGui.cs
index c9783999a5..c3480bfc27 100644
--- a/Content.Client/UserInterface/GhostGui.cs
+++ b/Content.Client/UserInterface/GhostGui.cs
@@ -54,41 +54,33 @@ namespace Content.Client.UserInterface
 
     public class GhostTargetWindow : SS14Window
     {
-        protected override Vector2? CustomSize => (300, 450);
         private readonly GhostComponent _owner;
         private readonly VBoxContainer _buttonContainer;
 
         public GhostTargetWindow(GhostComponent owner)
         {
+            MinSize = SetSize = (300, 450);
             Title = "Ghost Warp";
             _owner = owner;
             _owner.GhostRequestWarpPoint();
             _owner.GhostRequestPlayerNames();
 
-            var margin = new MarginContainer()
-            {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
-            };
-
             _buttonContainer = new VBoxContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.Fill,
+                VerticalExpand = true,
                 SeparationOverride = 5,
 
             };
 
             var scrollBarContainer = new ScrollContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                VerticalExpand = true,
+                HorizontalExpand = true
             };
 
-            margin.AddChild(scrollBarContainer);
             scrollBarContainer.AddChild(_buttonContainer);
 
-            Contents.AddChild(margin);
+            Contents.AddChild(scrollBarContainer);
         }
 
         public void Populate()
@@ -107,10 +99,10 @@ namespace Content.Client.UserInterface
                 {
                     Text = value,
                     TextAlign = Label.AlignMode.Right,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalAlignment = HAlignment.Center,
+                    VerticalAlignment = VAlignment.Center,
                     SizeFlagsStretchRatio = 1,
-                    CustomMinimumSize = (230, 20),
+                    MinSize = (230, 20),
                     ClipText = true,
                 };
 
@@ -131,10 +123,10 @@ namespace Content.Client.UserInterface
                 {
                     Text = $"Warp: {name}",
                     TextAlign = Label.AlignMode.Right,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                    HorizontalAlignment = HAlignment.Center,
+                    VerticalAlignment = VAlignment.Center,
                     SizeFlagsStretchRatio = 1,
-                    CustomMinimumSize = (230,20),
+                    MinSize = (230,20),
                     ClipText = true,
                 };
 
diff --git a/Content.Client/UserInterface/HumanoidProfileEditor.cs b/Content.Client/UserInterface/HumanoidProfileEditor.cs
index c1bfefeaa3..c38a5fc839 100644
--- a/Content.Client/UserInterface/HumanoidProfileEditor.cs
+++ b/Content.Client/UserInterface/HumanoidProfileEditor.cs
@@ -63,7 +63,8 @@ namespace Content.Client.UserInterface
         public HumanoidCharacterProfile Profile;
         public event Action<HumanoidCharacterProfile> OnProfileChanged;
 
-        public HumanoidProfileEditor(IClientPreferencesManager preferencesManager, IPrototypeManager prototypeManager, IEntityManager entityManager)
+        public HumanoidProfileEditor(IClientPreferencesManager preferencesManager, IPrototypeManager prototypeManager,
+            IEntityManager entityManager)
         {
             _random = IoCManager.Resolve<IRobustRandom>();
             _prototypeManager = prototypeManager;
@@ -74,17 +75,9 @@ namespace Content.Client.UserInterface
             AddChild(hbox);
 
             #region Left
-            var margin = new MarginContainer
-            {
-                MarginTopOverride = 10,
-                MarginBottomOverride = 10,
-                MarginLeftOverride = 10,
-                MarginRightOverride = 10
-            };
-            hbox.AddChild(margin);
 
-            var vBox = new VBoxContainer();
-            margin.AddChild(vBox);
+            var vBox = new VBoxContainer {Margin = new Thickness(10)};
+            hbox.AddChild(vBox);
 
             var middleContainer = new HBoxContainer
             {
@@ -116,13 +109,13 @@ namespace Content.Client.UserInterface
                 var panel = HighlightedContainer();
                 var hBox = new HBoxContainer
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand
+                    VerticalExpand = true
                 };
-                var nameLabel = new Label { Text = Loc.GetString("Name:") };
+                var nameLabel = new Label {Text = Loc.GetString("Name:")};
                 _nameEdit = new LineEdit
                 {
-                    CustomMinimumSize = (270, 0),
-                    SizeFlagsVertical = SizeFlags.ShrinkCenter
+                    MinSize = (270, 0),
+                    VerticalAlignment = VAlignment.Center
                 };
                 _nameEdit.OnTextChanged += args => { SetName(args.Text); };
                 var nameRandomButton = new Button
@@ -139,7 +132,7 @@ namespace Content.Client.UserInterface
 
             #endregion Name
 
-            var tabContainer = new TabContainer { SizeFlagsVertical = SizeFlags.FillExpand };
+            var tabContainer = new TabContainer {VerticalExpand = true};
             vBox.AddChild(tabContainer);
 
             #region Appearance
@@ -161,7 +154,7 @@ namespace Content.Client.UserInterface
                 {
                     var panel = HighlightedContainer();
                     var hBox = new HBoxContainer();
-                    var sexLabel = new Label { Text = Loc.GetString("Sex:") };
+                    var sexLabel = new Label {Text = Loc.GetString("Sex:")};
 
                     var sexButtonGroup = new ButtonGroup();
 
@@ -209,8 +202,8 @@ namespace Content.Client.UserInterface
                 {
                     var panel = HighlightedContainer();
                     var hBox = new HBoxContainer();
-                    var ageLabel = new Label { Text = Loc.GetString("Age:") };
-                    _ageEdit = new LineEdit { CustomMinimumSize = (40, 0) };
+                    var ageLabel = new Label {Text = Loc.GetString("Age:")};
+                    _ageEdit = new LineEdit {MinSize = (40, 0)};
                     _ageEdit.OnTextChanged += args =>
                     {
                         if (!int.TryParse(args.Text, out var newAge))
@@ -230,7 +223,7 @@ namespace Content.Client.UserInterface
                 {
                     var panel = HighlightedContainer();
                     var hBox = new HBoxContainer();
-                    var genderLabel = new Label { Text = Loc.GetString("Pronouns:") };
+                    var genderLabel = new Label {Text = Loc.GetString("Pronouns:")};
 
                     _genderButton = new OptionButton();
 
@@ -257,7 +250,7 @@ namespace Content.Client.UserInterface
 
                 {
                     var panel = HighlightedContainer();
-                    panel.SizeFlagsHorizontal = SizeFlags.None;
+                    panel.HorizontalAlignment = HAlignment.Left;
                     var hairHBox = new HBoxContainer();
 
                     _hairPicker = new HairStylePicker();
@@ -316,7 +309,7 @@ namespace Content.Client.UserInterface
                 {
                     var panel = HighlightedContainer();
                     var hBox = new HBoxContainer();
-                    var clothingLabel = new Label { Text = Loc.GetString("Clothing:") };
+                    var clothingLabel = new Label {Text = Loc.GetString("Clothing:")};
 
                     _clothingButton = new OptionButton();
 
@@ -342,7 +335,7 @@ namespace Content.Client.UserInterface
                 {
                     var panel = HighlightedContainer();
                     var hBox = new HBoxContainer();
-                    var backpackLabel = new Label { Text = Loc.GetString("Backpack:") };
+                    var backpackLabel = new Label {Text = Loc.GetString("Backpack:")};
 
                     _backpackButton = new OptionButton();
 
@@ -379,7 +372,7 @@ namespace Content.Client.UserInterface
                         (_preferenceUnavailableButton = new OptionButton()),
                         new ScrollContainer
                         {
-                            SizeFlagsVertical = SizeFlags.FillExpand,
+                            VerticalExpand = true,
                             Children =
                             {
                                 jobList
@@ -433,7 +426,7 @@ namespace Content.Client.UserInterface
                             {
                                 category.AddChild(new Control
                                 {
-                                    CustomMinimumSize = new Vector2(0, 23),
+                                    MinSize = new Vector2(0, 23),
                                 });
                             }
 
@@ -498,7 +491,7 @@ namespace Content.Client.UserInterface
                     {
                         new ScrollContainer
                         {
-                            SizeFlagsVertical = SizeFlags.FillExpand,
+                            VerticalExpand = true,
                             Children =
                             {
                                 antagList
@@ -519,6 +512,7 @@ namespace Content.Client.UserInterface
                     {
                         continue;
                     }
+
                     var selector = new AntagPreferenceSelector(antag);
                     antagList.AddChild(selector);
                     _antagPreferences.Add(selector);
@@ -568,7 +562,7 @@ namespace Content.Client.UserInterface
                 _saveButton = new Button
                 {
                     Text = Loc.GetString("Save"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                    HorizontalAlignment = HAlignment.Center
                 };
                 _saveButton.OnPressed += args => { Save(); };
                 panel.AddChild(_saveButton);
@@ -581,19 +575,10 @@ namespace Content.Client.UserInterface
 
             #region Right
 
-            margin = new MarginContainer
-            {
-                MarginTopOverride = 10,
-                MarginBottomOverride = 10,
-                MarginLeftOverride = 10,
-                MarginRightOverride = 10
-            };
-            hbox.AddChild(margin);
-
             vBox = new VBoxContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                VerticalExpand = true,
+                HorizontalExpand = true,
             };
             hbox.AddChild(vBox);
 
@@ -605,8 +590,7 @@ namespace Content.Client.UserInterface
             // Front
             var box = new Control()
             {
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1f,
             };
             vBox.AddChild(box);
@@ -615,7 +599,7 @@ namespace Content.Client.UserInterface
                 Sprite = sprite,
                 Scale = (6, 6),
                 OverrideDirection = Direction.South,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1
             };
             box.AddChild(_previewSprite);
@@ -623,8 +607,7 @@ namespace Content.Client.UserInterface
             // Side
             box = new Control()
             {
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SizeFlagsStretchRatio = 1f,
             };
             vBox.AddChild(box);
@@ -633,7 +616,7 @@ namespace Content.Client.UserInterface
                 Sprite = sprite,
                 Scale = (6, 6),
                 OverrideDirection = Direction.East,
-                SizeFlagsVertical = SizeFlags.ShrinkCenter,
+                VerticalAlignment = VAlignment.Center,
                 SizeFlagsStretchRatio = 1
             };
             box.AddChild(_previewSpriteSide);
@@ -862,7 +845,8 @@ namespace Content.Client.UserInterface
 
                 if (job.Icon != null)
                 {
-                    var specifier = new SpriteSpecifier.Rsi(new ResourcePath("/Textures/Interface/Misc/job_icons.rsi"), job.Icon);
+                    var specifier = new SpriteSpecifier.Rsi(new ResourcePath("/Textures/Interface/Misc/job_icons.rsi"),
+                        job.Icon);
                     icon.Texture = specifier.Frame0();
                 }
 
@@ -871,7 +855,7 @@ namespace Content.Client.UserInterface
                     Children =
                     {
                         icon,
-                        new Label {Text = job.Name, CustomMinimumSize = (175, 0)},
+                        new Label {Text = job.Name, MinSize = (175, 0)},
                         _optionButton
                     }
                 });
@@ -918,6 +902,7 @@ namespace Content.Client.UserInterface
                     }
                 });
             }
+
             private void OnCheckBoxToggled(BaseButton.ButtonToggledEventArgs args)
             {
                 PreferenceChanged?.Invoke(Preference);
diff --git a/Content.Client/UserInterface/ItemSlotButton.cs b/Content.Client/UserInterface/ItemSlotButton.cs
index c56eac72bf..d9ce11e04a 100644
--- a/Content.Client/UserInterface/ItemSlotButton.cs
+++ b/Content.Client/UserInterface/ItemSlotButton.cs
@@ -8,7 +8,7 @@ using Robust.Shared.Maths;
 
 namespace Content.Client.UserInterface
 {
-    public class ItemSlotButton : MarginContainer
+    public class ItemSlotButton : Control
     {
         private const string HighlightShader = "SelectionOutlineInrange";
 
@@ -29,7 +29,7 @@ namespace Content.Client.UserInterface
 
         public ItemSlotButton(Texture texture, Texture storageTexture)
         {
-            CustomMinimumSize = (64, 64);
+            MinSize = (64, 64);
 
             AddChild(Button = new TextureRect
             {
@@ -41,7 +41,7 @@ namespace Content.Client.UserInterface
             AddChild(_highlightRect = new PanelContainer
             {
                 StyleClasses = { StyleNano.StyleClassHandSlotHighlight },
-                CustomMinimumSize = (32, 32),
+                MinSize = (32, 32),
                 Visible = false
             });
 
@@ -63,8 +63,8 @@ namespace Content.Client.UserInterface
             {
                 TextureNormal = storageTexture,
                 Scale = (0.75f, 0.75f),
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd,
-                SizeFlagsVertical = SizeFlags.ShrinkEnd,
+                HorizontalAlignment = HAlignment.Right,
+                VerticalAlignment = VAlignment.Bottom,
                 Visible = false,
             });
 
@@ -92,8 +92,6 @@ namespace Content.Client.UserInterface
 
             AddChild(CooldownDisplay = new CooldownGraphic
             {
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                SizeFlagsVertical = SizeFlags.Fill,
                 Visible = false,
             });
         }
diff --git a/Content.Client/UserInterface/ItemStatusPanel.cs b/Content.Client/UserInterface/ItemStatusPanel.cs
index 71905a7dfb..a7e0c1d495 100644
--- a/Content.Client/UserInterface/ItemStatusPanel.cs
+++ b/Content.Client/UserInterface/ItemStatusPanel.cs
@@ -64,7 +64,10 @@ namespace Content.Client.UserInterface
                     }
                 }
             });
-            SizeFlagsVertical = SizeFlags.ShrinkEnd;
+            VerticalAlignment = VAlignment.Bottom;
+
+            // TODO: Depending on if its a two-hand panel or not
+            MinSize = (150, 0);
         }
 
         /// <summary>
@@ -156,11 +159,5 @@ namespace Content.Client.UserInterface
                 _activeStatusComponents.Add((statusComponent, control));
             }
         }
-
-        // TODO: Depending on if its a two-hand panel or not
-        protected override Vector2 CalculateMinimumSize()
-        {
-            return Vector2.ComponentMax(base.CalculateMinimumSize(), (150, 0));
-        }
     }
 }
diff --git a/Content.Client/UserInterface/LateJoinGui.cs b/Content.Client/UserInterface/LateJoinGui.cs
index 019e459eeb..8daffbad8e 100644
--- a/Content.Client/UserInterface/LateJoinGui.cs
+++ b/Content.Client/UserInterface/LateJoinGui.cs
@@ -24,8 +24,6 @@ namespace Content.Client.UserInterface
         [Dependency] private readonly IClientConsoleHost _consoleHost = default!;
         [Dependency] private readonly IClientGameTicker _gameTicker = default!;
 
-        protected override Vector2? CustomSize => (360, 560);
-
         public event Action<string> SelectedId;
 
         private readonly Dictionary<string, JobButton> _jobButtons = new();
@@ -33,6 +31,7 @@ namespace Content.Client.UserInterface
 
         public LateJoinGui()
         {
+            MinSize = SetSize = (360, 560);
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("Late Join");
@@ -44,7 +43,7 @@ namespace Content.Client.UserInterface
                 {
                     new ScrollContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         Children =
                         {
                             jobList
@@ -77,7 +76,7 @@ namespace Content.Client.UserInterface
                         {
                             category.AddChild(new Control
                             {
-                                CustomMinimumSize = new Vector2(0, 23),
+                                MinSize = new Vector2(0, 23),
                             });
                         }
 
@@ -104,7 +103,7 @@ namespace Content.Client.UserInterface
 
                     var jobSelector = new HBoxContainer
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     };
 
                     var icon = new TextureRect
diff --git a/Content.Client/UserInterface/LobbyCharacterPreviewPanel.cs b/Content.Client/UserInterface/LobbyCharacterPreviewPanel.cs
index 3fff738e03..f01055a7b8 100644
--- a/Content.Client/UserInterface/LobbyCharacterPreviewPanel.cs
+++ b/Content.Client/UserInterface/LobbyCharacterPreviewPanel.cs
@@ -40,7 +40,7 @@ namespace Content.Client.UserInterface
             CharacterSetupButton = new Button
             {
                 Text = Loc.GetString("Customize"),
-                SizeFlagsHorizontal = SizeFlags.None
+                HorizontalAlignment = HAlignment.Left
             };
 
             _summaryLabel = new Label();
diff --git a/Content.Client/UserInterface/LobbyGui.xaml b/Content.Client/UserInterface/LobbyGui.xaml
index aafc2e28a6..fc41df0733 100644
--- a/Content.Client/UserInterface/LobbyGui.xaml
+++ b/Content.Client/UserInterface/LobbyGui.xaml
@@ -13,7 +13,7 @@
         <PanelContainer StyleClasses="AngleRect" />
         <VBoxContainer>
             <!-- Top row -->
-            <HBoxContainer CustomMinimumSize="0 40">
+            <HBoxContainer MinSize="0 40">
                 <MarginContainer MarginLeftOverride="8">
                     <Label StyleClasses="LabelHeadingBigger" VAlign="Center" Text="{Loc 'Lobby'}" />
                 </MarginContainer>
@@ -30,9 +30,9 @@
                 </PanelContainer.PanelOverride>
             </PanelContainer>
             <!-- Middle section with the two vertical panels -->
-            <HBoxContainer SizeFlagsVertical="FillExpand">
+            <HBoxContainer VerticalExpand="True">
                 <!-- Left panel -->
-                <VBoxContainer Name="CLeftPanelContainer" SizeFlagsHorizontal="FillExpand">
+                <VBoxContainer Name="CLeftPanelContainer" HorizontalExpand="True">
                     <cui:StripeBack>
                         <MarginContainer MarginLeftOverride="3" MarginRightOverride="3" MarginBottomOverride="3"
                                          MarginTopOverride="3">
@@ -40,39 +40,39 @@
                                 <Button Name="CObserveButton" Text="{Loc 'Observe'}" StyleClasses="ButtonBig" />
                                 <Label Name="CStartTime" Align="Right"
                                        FontColorOverride="{x:Static maths:Color.DarkGray}"
-                                       StyleClasses="LabelBig" SizeFlagsHorizontal="FillExpand" />
+                                       StyleClasses="LabelBig" HorizontalExpand="True" />
                                 <Button Name="CReadyButton" ToggleMode="True" Text="{Loc 'Ready Up'}"
                                         StyleClasses="ButtonBig" />
                             </HBoxContainer>
                         </MarginContainer>
                     </cui:StripeBack>
-                    <MarginContainer SizeFlagsVertical="FillExpand" MarginLeftOverride="3" MarginRightOverride="3"
+                    <MarginContainer VerticalExpand="True" MarginLeftOverride="3" MarginRightOverride="3"
                                      MarginBottomOverride="3"
                                      MarginTopOverride="3">
                         <chat:ChatBox Name="CChat" />
                     </MarginContainer>
                 </VBoxContainer>
                 <!-- Gold line -->
-                <PanelContainer CustomMinimumSize="2 0">
+                <PanelContainer MinSize="2 0">
                     <PanelContainer.PanelOverride>
                         <gfx:StyleBoxFlat BackgroundColor="{x:Static style:StyleNano.NanoGold}" />
                     </PanelContainer.PanelOverride>
                 </PanelContainer>
                 <!-- Right panel -->
-                <Control SizeFlagsHorizontal="FillExpand">
+                <Control HorizontalExpand="True">
                     <VBoxContainer>
                         <!-- Player list -->
                         <cui:NanoHeading Text="{Loc 'Online Players'}" />
-                        <MarginContainer SizeFlagsVertical="FillExpand"
+                        <MarginContainer VerticalExpand="True"
                                          MarginRightOverride="3" MarginLeftOverride="3"
                                          MarginBottomOverride="3" MarginTopOverride="3">
                             <cui:LobbyPlayerList Name="COnlinePlayerList"
-                                                 SizeFlagsHorizontal="FillExpand"
-                                                 SizeFlagsVertical="FillExpand" />
+                                                 HorizontalExpand="True"
+                                                 VerticalExpand="True" />
                         </MarginContainer>
                         <!-- Server info -->
                         <cui:NanoHeading Text="{Loc 'Server Info'}" />
-                        <MarginContainer SizeFlagsVertical="FillExpand"
+                        <MarginContainer VerticalExpand="True"
                                          MarginRightOverride="3" MarginLeftOverride="3"
                                          MarginBottomOverride="2" MarginTopOverride="3">
                             <cui:ServerInfo Name="CServerInfo" />
diff --git a/Content.Client/UserInterface/LobbyGui.xaml.cs b/Content.Client/UserInterface/LobbyGui.xaml.cs
index 77124b1e32..028f997253 100644
--- a/Content.Client/UserInterface/LobbyGui.xaml.cs
+++ b/Content.Client/UserInterface/LobbyGui.xaml.cs
@@ -30,13 +30,14 @@ namespace Content.Client.UserInterface
         {
             RobustXamlLoader.Load(this);
 
-            ServerName.SizeFlagsHorizontal = SizeFlags.Expand | SizeFlags.ShrinkCenter;
+            ServerName.HorizontalExpand = true;
+            ServerName.HorizontalAlignment = HAlignment.Center;
 
             CharacterPreview = new LobbyCharacterPreviewPanel(
                 entityManager,
                 preferencesManager)
             {
-                SizeFlagsHorizontal = SizeFlags.None
+                HorizontalAlignment = HAlignment.Left
             };
 
             CLeftPanelContainer.AddChild(CharacterPreview);
@@ -67,7 +68,7 @@ namespace Content.Client.UserInterface
         {
             var hbox = new HBoxContainer
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
             };
 
             // Player Name
@@ -88,7 +89,7 @@ namespace Content.Client.UserInterface
                         Text = name
                     }
                 },
-                SizeFlagsHorizontal = SizeFlags.FillExpand
+                HorizontalExpand = true
             });
             // Status
             hbox.AddChild(new PanelContainer()
@@ -108,7 +109,7 @@ namespace Content.Client.UserInterface
                         Text = status
                     }
                 },
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SizeFlagsStretchRatio = 0.2f,
             });
 
diff --git a/Content.Client/UserInterface/NanoHeading.cs b/Content.Client/UserInterface/NanoHeading.cs
index d0ac77e9e7..baf08ae0ed 100644
--- a/Content.Client/UserInterface/NanoHeading.cs
+++ b/Content.Client/UserInterface/NanoHeading.cs
@@ -20,7 +20,7 @@ namespace Content.Client.UserInterface
             };
             AddChild(_panel);
 
-            SizeFlagsHorizontal = SizeFlags.None;
+            HorizontalAlignment = HAlignment.Left;
         }
 
         public string Text
@@ -28,15 +28,5 @@ namespace Content.Client.UserInterface
             get => _label.Text;
             set => _label.Text = value;
         }
-
-        protected override Vector2 CalculateMinimumSize()
-        {
-            return _panel.CombinedMinimumSize;
-        }
-
-        protected override void LayoutUpdateOverride()
-        {
-            FitChildInBox(_panel, SizeBox);
-        }
     }
 }
diff --git a/Content.Client/UserInterface/OptionsMenu.Audio.cs b/Content.Client/UserInterface/OptionsMenu.Audio.cs
index e7f206b55d..2516d95430 100644
--- a/Content.Client/UserInterface/OptionsMenu.Audio.cs
+++ b/Content.Client/UserInterface/OptionsMenu.Audio.cs
@@ -5,6 +5,7 @@ using Robust.Client.UserInterface.Controls;
 using Robust.Shared;
 using Robust.Shared.Configuration;
 using Robust.Shared.Localization;
+using Robust.Shared.Maths;
 
 namespace Content.Client.UserInterface
 {
@@ -27,20 +28,24 @@ namespace Content.Client.UserInterface
 
                 var vBox = new VBoxContainer();
 
-                var contents = new VBoxContainer();
+                var contents = new VBoxContainer
+                {
+                    Margin = new Thickness(2, 2, 2, 0),
+                    VerticalExpand = true,
+                };
 
                 MasterVolumeSlider = new Slider
                 {
                     MinValue = 0.0f,
                     MaxValue = 100.0f,
-                    SizeFlagsHorizontal = SizeFlags.FillExpand,
-                    CustomMinimumSize = (80, 8),
+                    HorizontalExpand = true,
+                    MinSize = (80, 8),
                     Rounded = true
                 };
 
                 MasterVolumeLabel = new Label
                 {
-                    CustomMinimumSize = (48, 0),
+                    MinSize = (48, 0),
                     Align = Label.AlignMode.Right
                 };
 
@@ -48,20 +53,20 @@ namespace Content.Client.UserInterface
                 {
                     Children =
                     {
-                        new Control {CustomMinimumSize = (4, 0)},
+                        new Control {MinSize = (4, 0)},
                         new Label {Text = Loc.GetString("Master Volume:")},
-                        new Control {CustomMinimumSize = (8, 0)},
+                        new Control {MinSize = (8, 0)},
                         MasterVolumeSlider,
-                        new Control {CustomMinimumSize = (8, 0)},
+                        new Control {MinSize = (8, 0)},
                         MasterVolumeLabel,
-                        new Control { CustomMinimumSize = (4, 0) },
+                        new Control { MinSize = (4, 0) },
                     }
                 });
 
                 ApplyButton = new Button
                 {
                     Text = Loc.GetString("Apply"), TextAlign = Label.AlignMode.Center,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                    HorizontalAlignment = HAlignment.Right
                 };
 
                 vBox.AddChild(new Label
@@ -71,23 +76,13 @@ namespace Content.Client.UserInterface
                     StyleClasses = { StyleNano.StyleClassLabelKeyText }
                 });
 
-                vBox.AddChild(new MarginContainer
-                {
-                    MarginLeftOverride = 2,
-                    MarginTopOverride = 2,
-                    MarginRightOverride = 2,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    Children =
-                    {
-                        contents
-                    }
-                });
+                vBox.AddChild(contents);
 
                 ResetButton = new Button
                 {
                     Text = Loc.GetString("Reset all"),
                     StyleClasses = { StyleBase.ButtonCaution },
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                    HorizontalAlignment = HAlignment.Right
                 };
 
                 vBox.AddChild(new StripeBack
@@ -99,12 +94,12 @@ namespace Content.Client.UserInterface
                         new HBoxContainer
                         {
                             Align = BoxContainer.AlignMode.End,
-                            SizeFlagsHorizontal = SizeFlags.FillExpand,
-                            SizeFlagsVertical = SizeFlags.FillExpand,
+                            HorizontalExpand = true,
+                            VerticalExpand = true,
                             Children =
                             {
                                 ResetButton,
-                                new Control { CustomMinimumSize = (2, 0) },
+                                new Control { MinSize = (2, 0) },
                                 ApplyButton
                             }
                         }
diff --git a/Content.Client/UserInterface/OptionsMenu.Graphics.cs b/Content.Client/UserInterface/OptionsMenu.Graphics.cs
index 615f5a99ab..c3363ad57b 100644
--- a/Content.Client/UserInterface/OptionsMenu.Graphics.cs
+++ b/Content.Client/UserInterface/OptionsMenu.Graphics.cs
@@ -38,7 +38,11 @@ namespace Content.Client.UserInterface
                 _cfg = cfg;
                 var vBox = new VBoxContainer();
 
-                var contents = new VBoxContainer();
+                var contents = new VBoxContainer
+                {
+                    Margin = new Thickness(2, 2, 2, 0),
+                    VerticalExpand = true,
+                };
 
                 VSyncCheckBox = new CheckBox {Text = Loc.GetString("VSync")};
                 contents.AddChild(VSyncCheckBox);
@@ -48,7 +52,7 @@ namespace Content.Client.UserInterface
                 contents.AddChild(FullscreenCheckBox);
                 FullscreenCheckBox.OnToggled += OnCheckBoxToggled;
 
-                LightingPresetOption = new OptionButton {CustomMinimumSize = (100, 0)};
+                LightingPresetOption = new OptionButton {MinSize = (100, 0)};
                 LightingPresetOption.AddItem(Loc.GetString("Very Low"));
                 LightingPresetOption.AddItem(Loc.GetString("Low"));
                 LightingPresetOption.AddItem(Loc.GetString("Medium"));
@@ -60,7 +64,7 @@ namespace Content.Client.UserInterface
                     Children =
                     {
                         new Label {Text = Loc.GetString("Lighting Quality:")},
-                        new Control {CustomMinimumSize = (4, 0)},
+                        new Control {MinSize = (4, 0)},
                         LightingPresetOption
                     }
                 });
@@ -68,7 +72,7 @@ namespace Content.Client.UserInterface
                 ApplyButton = new Button
                 {
                     Text = Loc.GetString("Apply"), TextAlign = Label.AlignMode.Center,
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                    HorizontalAlignment = HAlignment.Right
                 };
 
                 var resourceCache = IoCManager.Resolve<IResourceCache>();
@@ -88,28 +92,18 @@ namespace Content.Client.UserInterface
                     Children =
                     {
                         new Label {Text = Loc.GetString("UI Scale:")},
-                        new Control {CustomMinimumSize = (4, 0)},
+                        new Control {MinSize = (4, 0)},
                         _uiScaleOption
                     }
                 });
 
                 contents.AddChild(new Placeholder(resourceCache)
                 {
-                    SizeFlagsVertical = SizeFlags.FillExpand,
+                    VerticalExpand = true,
                     PlaceholderText = "Viewport settings"
                 });
 
-                vBox.AddChild(new MarginContainer
-                {
-                    MarginLeftOverride = 2,
-                    MarginTopOverride = 2,
-                    MarginRightOverride = 2,
-                    SizeFlagsVertical = SizeFlags.FillExpand,
-                    Children =
-                    {
-                        contents
-                    }
-                });
+                vBox.AddChild(contents);
 
                 vBox.AddChild(new StripeBack
                 {
diff --git a/Content.Client/UserInterface/OptionsMenu.KeyRebind.cs b/Content.Client/UserInterface/OptionsMenu.KeyRebind.cs
index 4d4e4158ba..f5c1ae9e34 100644
--- a/Content.Client/UserInterface/OptionsMenu.KeyRebind.cs
+++ b/Content.Client/UserInterface/OptionsMenu.KeyRebind.cs
@@ -9,6 +9,7 @@ using Robust.Client.UserInterface.Controls;
 using Robust.Shared.Input;
 using Robust.Shared.IoC;
 using Robust.Shared.Localization;
+using Robust.Shared.Maths;
 using Robust.Shared.Timing;
 using Robust.Shared.Utility;
 
@@ -39,25 +40,15 @@ namespace Content.Client.UserInterface
                 IoCManager.InjectDependencies(this);
 
                 Button resetAllButton;
-                var vBox = new VBoxContainer();
+                var vBox = new VBoxContainer {Margin = new Thickness(2, 0, 0, 0)};
                 AddChild(new VBoxContainer
                 {
                     Children =
                     {
                         new ScrollContainer
                         {
-                            SizeFlagsVertical = SizeFlags.FillExpand,
-                            Children =
-                            {
-                                new MarginContainer
-                                {
-                                    MarginLeftOverride = 2,
-                                    Children =
-                                    {
-                                        vBox
-                                    }
-                                }
-                            }
+                            VerticalExpand = true,
+                            Children = {vBox}
                         },
 
                         new StripeBack
@@ -70,7 +61,7 @@ namespace Content.Client.UserInterface
                                 {
                                     Children =
                                     {
-                                        new Control {CustomMinimumSize = (2, 0)},
+                                        new Control {MinSize = (2, 0)},
                                         new Label
                                         {
                                             StyleClasses = {StyleBase.StyleClassLabelSubText},
@@ -80,7 +71,7 @@ namespace Content.Client.UserInterface
                                         {
                                             Text = "Reset ALL keybinds",
                                             StyleClasses = {StyleBase.ButtonCaution},
-                                            SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Expand
+                                            HorizontalAlignment = HAlignment.Right
                                         })
                                     }
                                 }
@@ -89,7 +80,7 @@ namespace Content.Client.UserInterface
                     }
                 });
 
-                resetAllButton.OnPressed += args =>
+                resetAllButton.OnPressed += _ =>
                 {
                     _deferCommands.Add(() =>
                     {
@@ -104,7 +95,7 @@ namespace Content.Client.UserInterface
                 {
                     if (!first)
                     {
-                        vBox.AddChild(new Control {CustomMinimumSize = (0, 8)});
+                        vBox.AddChild(new Control {MinSize = (0, 8)});
                     }
 
                     first = false;
@@ -409,22 +400,23 @@ namespace Content.Client.UserInterface
                     var name = new Label
                     {
                         Text = Loc.GetString(niceName),
-                        SizeFlagsHorizontal = SizeFlags.Expand
+                        HorizontalExpand = true,
+                        HorizontalAlignment = HAlignment.Left
                     };
 
                     BindButton1 = new BindButton(parent, this, StyleBase.ButtonOpenRight);
                     BindButton2 = new BindButton(parent, this, StyleBase.ButtonOpenLeft);
-                    ResetButton = new Button {Text = "Reset", StyleClasses = {StyleBase.ButtonCaution}};
+                    ResetButton = new Button {Text = Loc.GetString("Reset"), StyleClasses = {StyleBase.ButtonCaution}};
 
                     var hBox = new HBoxContainer
                     {
                         Children =
                         {
-                            new Control {CustomMinimumSize = (5, 0)},
+                            new Control {MinSize = (5, 0)},
                             name,
                             BindButton1,
                             BindButton2,
-                            new Control {CustomMinimumSize = (10, 0)},
+                            new Control {MinSize = (10, 0)},
                             ResetButton
                         }
                     };
@@ -464,7 +456,7 @@ namespace Content.Client.UserInterface
 
                     Button.OnKeyBindDown += ButtonOnOnKeyBindDown;
 
-                    CustomMinimumSize = (200, 0);
+                    MinSize = (200, 0);
                 }
 
                 private void ButtonOnOnKeyBindDown(GUIBoundKeyEventArgs args)
diff --git a/Content.Client/UserInterface/OptionsMenu.cs b/Content.Client/UserInterface/OptionsMenu.cs
index 45f16f043d..2bec2344a0 100644
--- a/Content.Client/UserInterface/OptionsMenu.cs
+++ b/Content.Client/UserInterface/OptionsMenu.cs
@@ -15,10 +15,9 @@ namespace Content.Client.UserInterface
         [Dependency] private readonly IConfigurationManager _configManager = default!;
         [Dependency] private readonly IClydeAudio _clydeAudio = default!;
 
-        protected override Vector2? CustomSize => (800, 450);
-
         public OptionsMenu()
         {
+            SetSize = MinSize = (800, 450);
             IoCManager.InjectDependencies(this);
 
             Title = Loc.GetString("Game Options");
diff --git a/Content.Client/UserInterface/ParticleAccelerator/ParticleAcceleratorControlMenu.cs b/Content.Client/UserInterface/ParticleAccelerator/ParticleAcceleratorControlMenu.cs
index 785777aacb..ca5b06fa9e 100644
--- a/Content.Client/UserInterface/ParticleAccelerator/ParticleAcceleratorControlMenu.cs
+++ b/Content.Client/UserInterface/ParticleAccelerator/ParticleAcceleratorControlMenu.cs
@@ -53,6 +53,7 @@ namespace Content.Client.ParticleAccelerator
 
         public ParticleAcceleratorControlMenu(ParticleAcceleratorBoundUserInterface owner)
         {
+            SetSize = (400, 300);
             _greyScaleShader = IoCManager.Resolve<IPrototypeManager>().Index<ShaderPrototype>("Greyscale").Instance();
 
             Owner = owner;
@@ -128,13 +129,14 @@ namespace Content.Client.ParticleAccelerator
             var closeButton = new TextureButton
             {
                 StyleClasses = {"windowCloseButton"},
-                SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                HorizontalAlignment = HAlignment.Right,
+                Margin = new Thickness(0, 0, 8, 0)
             };
             closeButton.OnPressed += args => Close();
 
             var serviceManual = new Label
             {
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
+                HorizontalAlignment = HAlignment.Center,
                 StyleClasses = {StyleBase.StyleClassLabelSubText},
                 Text = Loc.GetString("Refer to p.132 of service manual")
             };
@@ -144,10 +146,9 @@ namespace Content.Client.ParticleAccelerator
             {
                 Children =
                 {
-                    new MarginContainer
+                    new Control
                     {
-                        MarginLeftOverride = 2,
-                        MarginTopOverride = 2,
+                        Margin = new Thickness(2, 2, 0, 0),
                         Children =
                         {
                             new Label
@@ -156,185 +157,154 @@ namespace Content.Client.ParticleAccelerator
                                 FontOverride = font,
                                 FontColorOverride = StyleNano.NanoGold,
                             },
-                            new MarginContainer
-                            {
-                                MarginRightOverride = 8,
-                                Children =
-                                {
-                                    closeButton
-                                }
-                            }
+                            closeButton
                         }
                     },
                     new PanelContainer
                     {
                         PanelOverride = new StyleBoxFlat {BackgroundColor = StyleNano.NanoGold},
-                        CustomMinimumSize = (0, 2),
+                        MinSize = (0, 2),
                     },
                     new Control
                     {
-                        CustomMinimumSize = (0, 4)
+                        MinSize = (0, 4)
                     },
 
                     new HBoxContainer
                     {
-                        SizeFlagsVertical = SizeFlags.FillExpand,
+                        VerticalExpand = true,
                         Children =
                         {
-                            new MarginContainer
+                            new VBoxContainer
                             {
-                                MarginLeftOverride = 4,
-                                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                Margin = new Thickness(4, 0, 0, 0),
+                                HorizontalExpand = true,
                                 Children =
                                 {
-                                    new VBoxContainer
+                                    new HBoxContainer
                                     {
                                         Children =
                                         {
-                                            new HBoxContainer
+                                            new Label
                                             {
-                                                Children =
-                                                {
-                                                    new Label
-                                                    {
-                                                        Text = Loc.GetString("Power: "),
-                                                        SizeFlagsHorizontal = SizeFlags.Expand
-                                                    },
-                                                    _offButton,
-                                                    _onButton
-                                                }
+                                                Text = Loc.GetString("Power: "),
+                                                HorizontalExpand = true,
+                                                HorizontalAlignment = HAlignment.Left,
                                             },
-                                            new HBoxContainer
-                                            {
-                                                Children =
-                                                {
-                                                    new Label
-                                                    {
-                                                        Text = Loc.GetString("Strength: "),
-                                                        SizeFlagsHorizontal = SizeFlags.Expand
-                                                    },
-                                                    _stateSpinBox
-                                                }
-                                            },
-                                            new Control
-                                            {
-                                                CustomMinimumSize = (0, 10),
-                                            },
-                                            _drawLabel,
-                                            new Control
-                                            {
-                                                SizeFlagsVertical = SizeFlags.Expand
-                                            },
-                                            (_alarmControl = new VBoxContainer
-                                            {
-                                                Children =
-                                                {
-                                                    new Label
-                                                    {
-                                                        Text = Loc.GetString("PARTICLE STRENGTH\nLIMITER FAILURE"),
-                                                        FontColorOverride = Color.Red,
-                                                        Align = Label.AlignMode.Center
-                                                    },
-                                                    serviceManual
-                                                }
-                                            }),
+                                            _offButton,
+                                            _onButton
                                         }
-                                    }
-                                }
-                            },
-                            new MarginContainer
-                            {
-                                CustomMinimumSize = (186, 0),
-                                Children =
-                                {
-                                    new VBoxContainer
+                                    },
+                                    new HBoxContainer
                                     {
                                         Children =
                                         {
-                                            (_statusLabel = new Label
+                                            new Label
                                             {
-                                                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
-                                            }),
-                                            new Control
-                                            {
-                                                CustomMinimumSize = (0, 20)
+                                                Text = Loc.GetString("Strength: "),
+                                                HorizontalExpand = true,
+                                                HorizontalAlignment = HAlignment.Left,
                                             },
-                                            new PanelContainer
-                                            {
-                                                SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                                                PanelOverride = back2,
-                                                Children =
-                                                {
-                                                    new GridContainer
-                                                    {
-                                                        Columns = 3,
-                                                        VSeparationOverride = 0,
-                                                        HSeparationOverride = 0,
-                                                        Children =
-                                                        {
-                                                            new Control {CustomMinimumSize = imgSize},
-                                                            (_endCapTexture = Segment("end_cap")),
-                                                            new Control {CustomMinimumSize = imgSize},
-                                                            (_controlBoxTexture = Segment("control_box")),
-                                                            (_fuelChamberTexture = Segment("fuel_chamber")),
-                                                            new Control {CustomMinimumSize = imgSize},
-                                                            new Control {CustomMinimumSize = imgSize},
-                                                            (_powerBoxTexture = Segment("power_box")),
-                                                            new Control {CustomMinimumSize = imgSize},
-                                                            (_emitterLeftTexture = Segment("emitter_left")),
-                                                            (_emitterCenterTexture = Segment("emitter_center")),
-                                                            (_emitterRightTexture = Segment("emitter_right")),
-                                                        }
-                                                    }
-                                                }
-                                            },
-                                            (_scanButton = new Button
-                                            {
-                                                Text = Loc.GetString("Scan Parts"),
-                                                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
-                                            })
+                                            _stateSpinBox
                                         }
-                                    }
+                                    },
+                                    new Control
+                                    {
+                                        MinSize = (0, 10),
+                                    },
+                                    _drawLabel,
+                                    new Control
+                                    {
+                                        VerticalExpand = true,
+                                    },
+                                    (_alarmControl = new VBoxContainer
+                                    {
+                                        Children =
+                                        {
+                                            new Label
+                                            {
+                                                Text = Loc.GetString("PARTICLE STRENGTH\nLIMITER FAILURE"),
+                                                FontColorOverride = Color.Red,
+                                                Align = Label.AlignMode.Center
+                                            },
+                                            serviceManual
+                                        }
+                                    }),
                                 }
                             },
+                            new VBoxContainer
+                            {
+                                MinSize = (186, 0),
+                                Children =
+                                {
+                                    (_statusLabel = new Label
+                                    {
+                                        HorizontalAlignment = HAlignment.Center
+                                    }),
+                                    new Control
+                                    {
+                                        MinSize = (0, 20)
+                                    },
+                                    new PanelContainer
+                                    {
+                                        HorizontalAlignment = HAlignment.Center,
+                                        PanelOverride = back2,
+                                        Children =
+                                        {
+                                            new GridContainer
+                                            {
+                                                Columns = 3,
+                                                VSeparationOverride = 0,
+                                                HSeparationOverride = 0,
+                                                Children =
+                                                {
+                                                    new Control {MinSize = imgSize},
+                                                    (_endCapTexture = Segment("end_cap")),
+                                                    new Control {MinSize = imgSize},
+                                                    (_controlBoxTexture = Segment("control_box")),
+                                                    (_fuelChamberTexture = Segment("fuel_chamber")),
+                                                    new Control {MinSize = imgSize},
+                                                    new Control {MinSize = imgSize},
+                                                    (_powerBoxTexture = Segment("power_box")),
+                                                    new Control {MinSize = imgSize},
+                                                    (_emitterLeftTexture = Segment("emitter_left")),
+                                                    (_emitterCenterTexture = Segment("emitter_center")),
+                                                    (_emitterRightTexture = Segment("emitter_right")),
+                                                }
+                                            }
+                                        }
+                                    },
+                                    (_scanButton = new Button
+                                    {
+                                        Text = Loc.GetString("Scan Parts"),
+                                        HorizontalAlignment = HAlignment.Center
+                                    })
+                                }
+                            }
                         }
                     },
                     new StripeBack
                     {
                         Children =
                         {
-                            new MarginContainer
+                            new Label
                             {
-                                MarginLeftOverride = 4,
-                                MarginTopOverride = 4,
-                                MarginBottomOverride = 4,
-                                Children =
-                                {
-                                    new Label
-                                    {
-                                        Text = Loc.GetString("Ensure containment field is active before operation"),
-                                        SizeFlagsHorizontal = SizeFlags.ShrinkCenter,
-                                        StyleClasses = {StyleBase.StyleClassLabelSubText},
-                                    }
-                                }
+                                Margin = new Thickness(4, 4, 0, 4),
+                                Text = Loc.GetString("Ensure containment field is active before operation"),
+                                HorizontalAlignment = HAlignment.Center,
+                                StyleClasses = {StyleBase.StyleClassLabelSubText},
                             }
                         }
                     },
-                    new MarginContainer
+                    new HBoxContainer
                     {
-                        MarginLeftOverride = 12,
+                        Margin = new Thickness(12, 0, 0, 0),
                         Children =
                         {
-                            new HBoxContainer
+                            new Label
                             {
-                                Children =
-                                {
-                                    new Label
-                                    {
-                                        Text = "FOO-BAR-BAZ",
-                                        StyleClasses = {StyleBase.StyleClassLabelSubText}
-                                    }
-                                }
+                                Text = "FOO-BAR-BAZ",
+                                StyleClasses = {StyleBase.StyleClassLabelSubText}
                             }
                         }
                     },
@@ -398,11 +368,6 @@ namespace Content.Client.ParticleAccelerator
             return DragMode.Move;
         }
 
-        protected override Vector2 CalculateMinimumSize()
-        {
-            return (400, 300);
-        }
-
         public void DataUpdate(ParticleAcceleratorUIState uiState)
         {
             _assembled = uiState.Assembled;
@@ -504,6 +469,7 @@ namespace Content.Client.ParticleAccelerator
 
                 AddChild(_base = new TextureRect {Texture = _rsi[$"{name}c"].Frame0});
                 AddChild(_unlit = new TextureRect());
+                MinSize = _rsi.Size;
             }
 
             public void SetPowerState(ParticleAcceleratorUIState state, bool exists)
@@ -537,11 +503,6 @@ namespace Content.Client.ParticleAccelerator
 
                 _unlit.Texture = rState.Frame0;
             }
-
-            protected override Vector2 CalculateMinimumSize()
-            {
-                return _rsi.Size;
-            }
         }
     }
 }
diff --git a/Content.Client/UserInterface/Permissions/PermissionsEui.cs b/Content.Client/UserInterface/Permissions/PermissionsEui.cs
index d6f8b7e190..2988352950 100644
--- a/Content.Client/UserInterface/Permissions/PermissionsEui.cs
+++ b/Content.Client/UserInterface/Permissions/PermissionsEui.cs
@@ -246,7 +246,8 @@ namespace Content.Client.UserInterface.Permissions
                 al.AddChild(new Label
                 {
                     Text = flagsText,
-                    SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter | Control.SizeFlags.Expand
+                    HorizontalExpand = true,
+                    HorizontalAlignment = Control.HAlignment.Center,
                 });
 
                 var editButton = new Button {Text = Loc.GetString("Edit")};
@@ -269,7 +270,8 @@ namespace Content.Client.UserInterface.Permissions
                 _menu.AdminRanksList.AddChild(new Label
                 {
                     Text = flagsText,
-                    SizeFlagsHorizontal = Control.SizeFlags.ShrinkCenter | Control.SizeFlags.Expand
+                    HorizontalExpand = true,
+                    HorizontalAlignment = Control.HAlignment.Center,
                 });
                 var editButton = new Button {Text = Loc.GetString("Edit")};
                 editButton.OnPressed += _ => OnEditRankPressed(kv);
@@ -306,16 +308,16 @@ namespace Content.Client.UserInterface.Permissions
                 AddAdminButton = new Button
                 {
                     Text = Loc.GetString("Add Admin"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                    HorizontalAlignment = HAlignment.Right
                 };
 
                 AddAdminRankButton = new Button
                 {
                     Text = Loc.GetString("Add Admin Rank"),
-                    SizeFlagsHorizontal = SizeFlags.ShrinkEnd
+                    HorizontalAlignment = HAlignment.Right
                 };
 
-                AdminsList = new GridContainer {Columns = 5, SizeFlagsVertical = SizeFlags.FillExpand};
+                AdminsList = new GridContainer {Columns = 5, VerticalExpand = true};
                 var adminVBox = new VBoxContainer
                 {
                     Children = {AdminsList, AddAdminButton},
@@ -352,6 +354,7 @@ namespace Content.Client.UserInterface.Permissions
 
             public EditAdminWindow(PermissionsEui ui, PermissionsEuiState.AdminData? data)
             {
+                SetSize = MinSize = (600, 400);
                 SourceData = data;
 
                 Control nameControl;
@@ -372,7 +375,7 @@ namespace Content.Client.UserInterface.Permissions
 
                 TitleEdit = new LineEdit {PlaceHolder = Loc.GetString("Custom title, leave blank to inherit rank title.")};
                 RankButton = new OptionButton();
-                SaveButton = new Button {Text = Loc.GetString("Save"), SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Expand};
+                SaveButton = new Button {Text = Loc.GetString("Save"), HorizontalAlignment = HAlignment.Right};
 
                 RankButton.AddItem(Loc.GetString("No rank"), NoRank);
                 foreach (var (rId, rank) in ui._ranks)
@@ -470,7 +473,7 @@ namespace Content.Client.UserInterface.Permissions
                             {
                                 new VBoxContainer
                                 {
-                                    SizeFlagsHorizontal = SizeFlags.FillExpand,
+                                    HorizontalExpand = true,
                                     Children =
                                     {
                                         nameControl,
@@ -480,7 +483,7 @@ namespace Content.Client.UserInterface.Permissions
                                 },
                                 permGrid
                             },
-                            SizeFlagsVertical = SizeFlags.FillExpand
+                            VerticalExpand = true
                         },
                         bottomButtons
                     }
@@ -509,8 +512,6 @@ namespace Content.Client.UserInterface.Permissions
                     }
                 }
             }
-
-            protected override Vector2? CustomSize => (600, 400);
         }
 
         private sealed class EditAdminRankWindow : SS14Window
@@ -523,6 +524,7 @@ namespace Content.Client.UserInterface.Permissions
 
             public EditAdminRankWindow(PermissionsEui ui, KeyValuePair<int, PermissionsEuiState.AdminRankData>? data)
             {
+                MinSize = SetSize = (600, 400);
                 SourceId = data?.Key;
 
                 NameEdit = new LineEdit
@@ -535,7 +537,11 @@ namespace Content.Client.UserInterface.Permissions
                     NameEdit.Text = data.Value.Value.Name;
                 }
 
-                SaveButton = new Button {Text = Loc.GetString("Save"), SizeFlagsHorizontal = SizeFlags.ShrinkEnd | SizeFlags.Expand};
+                SaveButton = new Button {
+                    Text = Loc.GetString("Save"),
+                    HorizontalAlignment = HAlignment.Right,
+                    HorizontalExpand = true
+                };
                 var flagsBox = new VBoxContainer();
 
                 foreach (var flag in AdminFlagsHelper.AllFlags)
@@ -594,8 +600,6 @@ namespace Content.Client.UserInterface.Permissions
 
                 return flags;
             }
-
-            protected override Vector2? CustomSize => (600, 400);
         }
     }
 }
diff --git a/Content.Client/UserInterface/Placeholder.cs b/Content.Client/UserInterface/Placeholder.cs
index 6ffeda1c42..adef4ac728 100644
--- a/Content.Client/UserInterface/Placeholder.cs
+++ b/Content.Client/UserInterface/Placeholder.cs
@@ -19,8 +19,7 @@ namespace Content.Client.UserInterface
         {
             _label = new Label
             {
-                SizeFlagsHorizontal = SizeFlags.Fill,
-                SizeFlagsVertical = SizeFlags.Fill,
+                VerticalAlignment = VAlignment.Stretch,
                 Align = Label.AlignMode.Center,
                 VAlign = Label.VAlignMode.Center
             };
diff --git a/Content.Client/UserInterface/RoundEndSummaryWindow.cs b/Content.Client/UserInterface/RoundEndSummaryWindow.cs
index 738424aa73..c4b3726e3e 100644
--- a/Content.Client/UserInterface/RoundEndSummaryWindow.cs
+++ b/Content.Client/UserInterface/RoundEndSummaryWindow.cs
@@ -2,11 +2,9 @@
 using System.Collections.Generic;
 using System.Linq;
 using Content.Client.Utility;
-using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
 using Robust.Shared.Localization;
-using Robust.Shared.Maths;
 using static Content.Shared.GameTicking.SharedGameTicker;
 
 namespace Content.Client.UserInterface
@@ -16,10 +14,10 @@ namespace Content.Client.UserInterface
         private VBoxContainer RoundEndSummaryTab { get; }
         private VBoxContainer PlayerManifestoTab { get; }
         private TabContainer RoundEndWindowTabs { get; }
-        protected override Vector2? CustomSize => (520, 580);
 
         public RoundEndSummaryWindow(string gm, string roundEnd, TimeSpan roundTimeSpan, List<RoundEndPlayerInfo> info)
         {
+            MinSize = SetSize = (520, 580);
 
             Title = Loc.GetString("Round End Summary");
 
@@ -66,7 +64,7 @@ namespace Content.Client.UserInterface
 
             //Initialize what will be the list of players display.
             var scrollContainer = new ScrollContainer();
-            scrollContainer.SizeFlagsVertical = SizeFlags.FillExpand;
+            scrollContainer.VerticalExpand = true;
             var innerScrollContainer = new VBoxContainer();
 
             //Put observers at the bottom of the list. Put antags on top.
@@ -74,10 +72,7 @@ namespace Content.Client.UserInterface
             //Create labels for each player info.
             foreach (var playerInfo in manifestSortedList)
             {
-                var playerInfoText = new RichTextLabel()
-                {
-                    SizeFlagsVertical = SizeFlags.Fill,
-                };
+                var playerInfoText = new RichTextLabel();
 
                 if (playerInfo.Observer)
                 {
@@ -100,23 +95,11 @@ namespace Content.Client.UserInterface
             scrollContainer.AddChild(innerScrollContainer);
             //Attach the entire ScrollContainer that holds all the playerinfo.
             PlayerManifestoTab.AddChild(scrollContainer);
-            // TODO: 1240 Overlap, remove once it's fixed. Temp Hack to make the lines not overlap
-            PlayerManifestoTab.OnVisibilityChanged += PlayerManifestoTab_OnVisibilityChanged;
 
             //Finally, display the window.
             OpenCentered();
             MoveToFront();
         }
-
-        private void PlayerManifestoTab_OnVisibilityChanged(Control obj)
-        {
-            if (obj.Visible)
-            {
-                // For some reason the lines get not properly drawn with the right height
-                // so we just force a update
-                ForceRunLayoutUpdate();
-            }
-        }
     }
 
 }
diff --git a/Content.Client/UserInterface/ServerInfo.cs b/Content.Client/UserInterface/ServerInfo.cs
index 5bf1a7b91f..bb29cd6ded 100644
--- a/Content.Client/UserInterface/ServerInfo.cs
+++ b/Content.Client/UserInterface/ServerInfo.cs
@@ -14,7 +14,7 @@ namespace Content.Client.UserInterface
         {
             _richTextLabel = new RichTextLabel
             {
-                SizeFlagsVertical = SizeFlags.FillExpand
+                VerticalExpand = true
             };
             AddChild(_richTextLabel);
 
diff --git a/Content.Client/UserInterface/StripeBack.cs b/Content.Client/UserInterface/StripeBack.cs
index 51e77e010f..2f5d965364 100644
--- a/Content.Client/UserInterface/StripeBack.cs
+++ b/Content.Client/UserInterface/StripeBack.cs
@@ -21,8 +21,8 @@ namespace Content.Client.UserInterface
             get => _hasTopEdge;
             set
             {
-                MinimumSizeChanged();
                 _hasTopEdge = value;
+                InvalidateMeasure();
             }
         }
 
@@ -32,7 +32,7 @@ namespace Content.Client.UserInterface
             set
             {
                 _hasBottomEdge = value;
-                MinimumSizeChanged();
+                InvalidateMeasure();
             }
         }
 
@@ -42,37 +42,36 @@ namespace Content.Client.UserInterface
             set
             {
                 _hasMargins = value;
-                MinimumSizeChanged();
+                InvalidateMeasure();
             }
         }
 
-        protected override Vector2 CalculateMinimumSize()
+        protected override Vector2 MeasureOverride(Vector2 availableSize)
         {
+            var padSize = HasMargins ? PadSize : 0;
+            var padSizeTotal = 0f;
+
+            if (HasBottomEdge)
+                padSizeTotal += padSize + EdgeSize;
+            if (HasTopEdge)
+                padSizeTotal += padSize + EdgeSize;
+
             var size = Vector2.Zero;
 
+            availableSize.Y -= padSizeTotal;
+
             foreach (var child in Children)
             {
-                size = Vector2.ComponentMax(size, child.CombinedMinimumSize);
+                child.Measure(availableSize);
+                size = Vector2.ComponentMax(size, child.DesiredSize);
             }
 
-            var padSize = HasMargins ? PadSize : 0;
-
-            if (HasBottomEdge)
-            {
-                size += (0, padSize + EdgeSize);
-            }
-
-            if (HasTopEdge)
-            {
-                size += (0, padSize + EdgeSize);
-            }
-
-            return size;
+            return size + (0, padSizeTotal);
         }
 
-        protected override void LayoutUpdateOverride()
+        protected override Vector2 ArrangeOverride(Vector2 finalSize)
         {
-            var box = SizeBox;
+            var box = new UIBox2(Vector2.Zero, finalSize);
 
             var padSize = HasMargins ? PadSize : 0;
 
@@ -88,10 +87,13 @@ namespace Content.Client.UserInterface
 
             foreach (var child in Children)
             {
-                FitChildInBox(child, box);
+                child.Arrange(box);
             }
+
+            return finalSize;
         }
 
+
         protected override void Draw(DrawingHandleScreen handle)
         {
             UIBox2 centerBox = PixelSizeBox;
@@ -107,7 +109,8 @@ namespace Content.Client.UserInterface
             if (HasBottomEdge)
             {
                 centerBox += (0, 0, 0, -((padSize + EdgeSize) * UIScale));
-                handle.DrawRect(new UIBox2(0, centerBox.Bottom, PixelWidth, PixelHeight - padSize * UIScale), EdgeColor);
+                handle.DrawRect(new UIBox2(0, centerBox.Bottom, PixelWidth, PixelHeight - padSize * UIScale),
+                    EdgeColor);
             }
 
             GetActualStyleBox()?.Draw(handle, centerBox);
diff --git a/Content.Client/UserInterface/StrippingMenu.cs b/Content.Client/UserInterface/StrippingMenu.cs
index 50411b0040..18fb27dfa1 100644
--- a/Content.Client/UserInterface/StrippingMenu.cs
+++ b/Content.Client/UserInterface/StrippingMenu.cs
@@ -9,17 +9,16 @@ namespace Content.Client.UserInterface
 {
     public class StrippingMenu : SS14Window
     {
-        protected override Vector2? CustomSize => new Vector2(400, 600);
-
         private readonly VBoxContainer _vboxContainer;
 
         public StrippingMenu(string title)
         {
+            MinSize = SetSize = (400, 600);
             Title = title;
 
             _vboxContainer = new VBoxContainer()
             {
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
                 SeparationOverride = 5,
             };
 
@@ -43,7 +42,7 @@ namespace Content.Client.UserInterface
 
             _vboxContainer.AddChild(new HBoxContainer()
             {
-                SizeFlagsHorizontal = SizeFlags.FillExpand,
+                HorizontalExpand = true,
                 SeparationOverride = 5,
                 Children =
                 {
@@ -53,7 +52,7 @@ namespace Content.Client.UserInterface
                     },
                     new Control()
                     {
-                        SizeFlagsHorizontal = SizeFlags.FillExpand
+                        HorizontalExpand = true
                     },
                     button,
                 }
diff --git a/Content.Client/UserInterface/Suspicion/SuspicionGui.xaml.cs b/Content.Client/UserInterface/Suspicion/SuspicionGui.xaml.cs
index e0a75fd994..157687cc01 100644
--- a/Content.Client/UserInterface/Suspicion/SuspicionGui.xaml.cs
+++ b/Content.Client/UserInterface/Suspicion/SuspicionGui.xaml.cs
@@ -35,7 +35,7 @@ namespace Content.Client.UserInterface.Suspicion
             IoCManager.InjectDependencies(this);
 
             RoleButton.OnPressed += RoleButtonPressed;
-            RoleButton.CustomMinimumSize = (200, 60);
+            RoleButton.MinSize = (200, 60);
         }
 
         private void RoleButtonPressed(ButtonEventArgs obj)
diff --git a/Content.Client/UserInterface/TargetingDoll.cs b/Content.Client/UserInterface/TargetingDoll.cs
index 762b73744a..db138e3d8b 100644
--- a/Content.Client/UserInterface/TargetingDoll.cs
+++ b/Content.Client/UserInterface/TargetingDoll.cs
@@ -44,21 +44,21 @@ namespace Content.Client.UserInterface
             {
                 TextureNormal = resourceCache.GetTexture(TextureHigh),
                 StyleClasses = {StyleClassTargetDollZone},
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center
             };
 
             _buttonMiddle = new TextureButton
             {
                 TextureNormal = resourceCache.GetTexture(TextureMiddle),
                 StyleClasses = {StyleClassTargetDollZone},
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center
             };
 
             _buttonLow = new TextureButton
             {
                 TextureNormal = resourceCache.GetTexture(TextureLow),
                 StyleClasses = {StyleClassTargetDollZone},
-                SizeFlagsHorizontal = SizeFlags.ShrinkCenter
+                HorizontalAlignment = HAlignment.Center
             };
 
             _buttonHigh.OnPressed += _ => ActiveZone = TargetingZone.High;
diff --git a/Content.Client/UserInterface/TutorialWindow.cs b/Content.Client/UserInterface/TutorialWindow.cs
index c644360047..ee7e98c01c 100644
--- a/Content.Client/UserInterface/TutorialWindow.cs
+++ b/Content.Client/UserInterface/TutorialWindow.cs
@@ -36,10 +36,9 @@ namespace Content.Client.UserInterface
 [color=#a4885c]AlignWall[/color] snaps to vertical halftiles.
 [color=#a4885c]AlignWallProper[/color] snaps the entity to the middle of the tile edges";
 
-        protected override Vector2? CustomSize => (520, 580);
-
         public TutorialWindow()
         {
+            MinSize = SetSize = (520, 580);
             Title = "The Tutorial!";
 
             //Get section header font
diff --git a/Content.Client/VendingMachines/VendingMachineMenu.cs b/Content.Client/VendingMachines/VendingMachineMenu.cs
index 0dca214eda..2becd88f38 100644
--- a/Content.Client/VendingMachines/VendingMachineMenu.cs
+++ b/Content.Client/VendingMachines/VendingMachineMenu.cs
@@ -17,8 +17,6 @@ namespace Content.Client.VendingMachines
         [Dependency] private readonly IResourceCache _resourceCache = default!;
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
 
-        protected override Vector2? CustomSize => (300, 450);
-
         private readonly ItemList _items;
         private List<VendingMachineInventoryEntry> _cachedInventory;
 
@@ -26,12 +24,13 @@ namespace Content.Client.VendingMachines
 
         public VendingMachineMenu()
         {
+            SetSize = MinSize = (300, 450);
             IoCManager.InjectDependencies(this);
 
             _items = new ItemList()
             {
                 SizeFlagsStretchRatio = 8,
-                SizeFlagsVertical = SizeFlags.FillExpand,
+                VerticalExpand = true,
             };
             _items.OnItemSelected += ItemSelected;
 
diff --git a/Content.Client/Voting/VoteCallMenu.xaml b/Content.Client/Voting/VoteCallMenu.xaml
index b587921735..7fa7f2ade0 100644
--- a/Content.Client/Voting/VoteCallMenu.xaml
+++ b/Content.Client/Voting/VoteCallMenu.xaml
@@ -1,11 +1,11 @@
 <v:VoteCallMenu xmlns="https://spacestation14.io"
                 xmlns:cuic="clr-namespace:Content.Client.UserInterface.Controls"
                 xmlns:v="clr-namespace:Content.Client.Voting"
-                MouseFilter="Stop" CustomMinimumSize="350 150">
+                MouseFilter="Stop" MinSize="350 150">
     <PanelContainer StyleClasses="AngleRect" />
     <VBoxContainer>
         <HBoxContainer>
-            <MarginContainer MarginLeftOverride="8" SizeFlagsHorizontal="FillExpand">
+            <MarginContainer MarginLeftOverride="8" HorizontalExpand="True">
                 <Label Text="{Loc 'Call Vote'}" VAlign="Center" StyleClasses="LabelHeading" />
             </MarginContainer>
             <MarginContainer MarginRightOverride="8">
@@ -18,8 +18,8 @@
         <MarginContainer SizeFlagsHorizontal="Fill" SizeFlagsVertical="Expand"
                          MarginLeftOverride="8" MarginRightOverride="8" MarginTopOverride="2">
             <HBoxContainer>
-                <OptionButton Name="VoteTypeButton" SizeFlagsHorizontal="FillExpand" />
-                <Control SizeFlagsHorizontal="FillExpand">
+                <OptionButton Name="VoteTypeButton" HorizontalExpand="True" />
+                <Control HorizontalExpand="True">
                     <OptionButton Name="VoteSecondButton" Visible="False" />
                 </Control>
             </HBoxContainer>
diff --git a/Content.Client/Voting/VotePopup.xaml b/Content.Client/Voting/VotePopup.xaml
index e5e3faaee2..b33c4aaa36 100644
--- a/Content.Client/Voting/VotePopup.xaml
+++ b/Content.Client/Voting/VotePopup.xaml
@@ -7,7 +7,7 @@
 
             <GridContainer Columns="3" Name="VoteOptionsContainer" />
             <HBoxContainer>
-                <MarginContainer SizeFlagsHorizontal="FillExpand" MarginLeftOverride="2" MarginRightOverride="2"
+                <MarginContainer HorizontalExpand="True" MarginLeftOverride="2" MarginRightOverride="2"
                                      MarginTopOverride="2" MarginBottomOverride="2">
                     <ProgressBar Name="TimeLeftBar" MinValue="0" MaxValue="1" />
                 </MarginContainer>