From 6b0c4e8ca892bf3c30611e6b3bc3a84c391b81d0 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Sat, 13 Jun 2026 22:41:58 +0300
Subject: [PATCH 1/7] Hello world!

---
 Content.Client/Decals/DecalPlacementSystem.cs | 94 +++++++++++++++++++
 .../Decals/Overlays/DecalPlacementOverlay.cs  | 38 ++++++++
 .../Decals/UI/DecalPlacerWindow.xaml          |  2 +
 .../Decals/UI/DecalPlacerWindow.xaml.cs       | 35 +++++++
 .../en-US/_Exodus/decals/decal-window.ftl     |  1 +
 .../ru-RU/_Exodus/decals/decal-window.ftl     |  1 +
 6 files changed, 171 insertions(+)
 create mode 100644 Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
 create mode 100644 Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl

diff --git a/Content.Client/Decals/DecalPlacementSystem.cs b/Content.Client/Decals/DecalPlacementSystem.cs
index ac39182ac68..dfb4a16a4c7 100644
--- a/Content.Client/Decals/DecalPlacementSystem.cs
+++ b/Content.Client/Decals/DecalPlacementSystem.cs
@@ -8,6 +8,7 @@
 using Robust.Client.Input;
 using Robust.Shared.Input;
 using Robust.Shared.Input.Binding;
+using Robust.Shared.Map; // Exodus
 using Robust.Shared.Prototypes;
 
 namespace Content.Client.Decals;
@@ -17,6 +18,7 @@ namespace Content.Client.Decals;
 public sealed partial class DecalPlacementSystem : EntitySystem
 {
     [Dependency] private IInputManager _inputManager = default!;
+    [Dependency] private IMapManager _mapManager = default!; // Exodus
     [Dependency] private IOverlayManager _overlay = default!;
     [Dependency] private IPrototypeManager _protoMan = default!;
     [Dependency] private InputSystem _inputSystem = default!;
@@ -35,6 +37,25 @@ public sealed partial class DecalPlacementSystem : EntitySystem
     private bool _placing;
     private bool _erasing;
 
+    // Exodus-Start: eyedropper tool that copies the color of an existing decal on the map.
+    private bool _eyedropper;
+
+    /// <summary>
+    ///     Whether the eyedropper (color picker) tool is currently selected.
+    /// </summary>
+    public bool EyedropperActive => _eyedropper;
+
+    /// <summary>
+    ///     Raised when the eyedropper successfully copies a color from a decal on the map.
+    /// </summary>
+    public event Action<Color>? EyedropperPicked;
+
+    public void SetEyedropper(bool active)
+    {
+        _eyedropper = active && _active;
+    }
+    // Exodus-End
+
     public (DecalPrototype? Decal, bool Snap, Angle Angle, Color Color) GetActiveDecal()
     {
         return _active && _decalId != null ?
@@ -50,6 +71,18 @@ public override void Initialize()
         CommandBinds.Builder.Bind(EngineKeyFunctions.EditorPlaceObject, new PointerStateInputCmdHandler(
             (session, coords, uid) =>
             {
+                // Exodus-Start: left click while the eyedropper is active copies a color instead of placing.
+                if (_eyedropper)
+                {
+                    _eyedropper = false;
+
+                    if (TryPickDecalColor(coords, out var picked))
+                        EyedropperPicked?.Invoke(picked);
+
+                    return true;
+                }
+                // Exodus-End
+
                 if (!_active || _placing || _decalId == null)
                     return false;
 
@@ -85,6 +118,14 @@ public override void Initialize()
             .Bind(EngineKeyFunctions.EditorCancelPlace, new PointerStateInputCmdHandler(
             (session, coords, uid) =>
             {
+                // Exodus-Start: right click cancels the eyedropper instead of erasing.
+                if (_eyedropper)
+                {
+                    _eyedropper = false;
+                    return true;
+                }
+                // Exodus-End
+
                 if (!_active || _erasing)
                     return false;
 
@@ -189,12 +230,65 @@ public void UpdateDecalInfo(string id, Color color, float rotation, bool snap, i
         _cleanable = cleanable;
     }
 
+    // Exodus: clear the active decal so it stops following the cursor when deselected.
+    public void ClearDecal()
+    {
+        _decalId = null;
+    }
+
     public void SetActive(bool active)
     {
         _active = active;
+        _eyedropper = false; // Exodus: arming is always an explicit user action.
         if (_active)
             _inputManager.Contexts.SetActiveContext("editor");
         else
             _inputSystem.SetEntityContextActive();
     }
+
+    // Exodus-Start: find the topmost decal under the given coordinates and return its color.
+    private bool TryPickDecalColor(EntityCoordinates coords, out Color color)
+    {
+        color = Color.White;
+
+        var mapPos = _transform.ToMapCoordinates(coords);
+        if (!_mapManager.TryFindGridAt(mapPos, out var gridUid, out _))
+            return false;
+
+        if (!TryComp<DecalGridComponent>(gridUid, out var decalGrid))
+            return false;
+
+        var localPos = Vector2.Transform(mapPos.Position, _transform.GetInvWorldMatrix(gridUid));
+        var chunkIndices = SharedDecalSystem.GetChunkIndices(localPos);
+
+        if (!decalGrid.ChunkCollection.ChunkCollection.TryGetValue(chunkIndices, out var chunk))
+            return false;
+
+        Decal? best = null;
+        var bestZ = int.MinValue;
+        var bestId = 0u;
+
+        foreach (var (id, decal) in chunk.Decals)
+        {
+            // Decals are drawn as a 1x1 tile with their bottom-left corner at Coordinates.
+            if (localPos.X < decal.Coordinates.X || localPos.X >= decal.Coordinates.X + 1f ||
+                localPos.Y < decal.Coordinates.Y || localPos.Y >= decal.Coordinates.Y + 1f)
+                continue;
+
+            // Match the overlay's draw order: highest ZIndex, then highest id, is on top.
+            if (best != null && (decal.ZIndex < bestZ || decal.ZIndex == bestZ && id < bestId))
+                continue;
+
+            best = decal;
+            bestZ = decal.ZIndex;
+            bestId = id;
+        }
+
+        if (best == null)
+            return false;
+
+        color = best.Color ?? Color.White;
+        return true;
+    }
+    // Exodus-End
 }
diff --git a/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs b/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
index e0e73af5f79..40bd026ff91 100644
--- a/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
+++ b/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
@@ -30,6 +30,14 @@ public DecalPlacementOverlay(DecalPlacementSystem placement, SharedTransformSyst
 
     protected override void Draw(in OverlayDrawArgs args)
     {
+        // Exodus-Start: draw the eyedropper crosshair instead of a decal preview while picking a color.
+        if (_placement.EyedropperActive)
+        {
+            DrawEyedropper(args);
+            return;
+        }
+        // Exodus-End
+
         var (decal, snap, rotation, color) = _placement.GetActiveDecal();
 
         if (decal == null)
@@ -67,4 +75,34 @@ protected override void Draw(in OverlayDrawArgs args)
         handle.DrawTextureRect(_sprite.Frame0(decal.Sprite), box, color);
         handle.SetTransform(Matrix3x2.Identity);
     }
+
+    // Exodus-Start: crosshair shown at the cursor marking the sample point of the eyedropper tool.
+    private void DrawEyedropper(in OverlayDrawArgs args)
+    {
+        var mouseScreenPos = _inputManager.MouseScreenPosition;
+        var mousePos = _eyeManager.PixelToMap(mouseScreenPos);
+
+        if (mousePos.MapId != args.MapId)
+            return;
+
+        // The handle is already in world space here (we never set a transform), so draw directly.
+        var handle = args.WorldHandle;
+        var pos = mousePos.Position;
+        const float arm = 0.35f;
+        const float gap = 0.08f;
+
+        // Draw a dark outline first so the crosshair stays visible over any decal color.
+        DrawCross(handle, pos, arm, gap, 0.04f, Color.Black.WithAlpha(0.6f));
+        DrawCross(handle, pos, arm, gap, 0f, Color.White);
+        handle.DrawCircle(pos, gap, Color.White, false);
+    }
+
+    private static void DrawCross(DrawingHandleWorld handle, Vector2 pos, float arm, float gap, float pad, Color color)
+    {
+        handle.DrawLine(pos + new Vector2(-arm - pad, 0f), pos + new Vector2(-gap + pad, 0f), color);
+        handle.DrawLine(pos + new Vector2(gap - pad, 0f), pos + new Vector2(arm + pad, 0f), color);
+        handle.DrawLine(pos + new Vector2(0f, -arm - pad), pos + new Vector2(0f, -gap + pad), color);
+        handle.DrawLine(pos + new Vector2(0f, gap - pad), pos + new Vector2(0f, arm + pad), color);
+    }
+    // Exodus-End
 }
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
index 0a4f2d67a6b..f9e8c8b58be 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
@@ -13,6 +13,8 @@
         <BoxContainer Orientation="Vertical">
             <ColorSelectorSliders Name="ColorPicker" IsAlphaVisible="True" />
             <Button Name="PickerOpen" Text="{Loc 'decal-placer-window-palette'}" />
+            <!-- Exodus: eyedropper tool, copies the color of a decal already on the map -->
+            <Button Name="EyedropperButton" Text="{Loc 'decal-placer-window-eyedropper'}" />
         </BoxContainer>
         <CheckBox Name="EnableAuto" Text="{Loc 'decal-placer-window-enable-auto'}" Margin="0 0 0 10"/>
         <CheckBox Name="EnableColor" Text="{Loc 'decal-placer-window-use-color'}" />
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
index 1625cb69a3b..030775e8e42 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
@@ -53,6 +53,12 @@ public DecalPlacerWindow()
         Search.OnTextChanged += _ => RefreshList();
         ColorPicker.OnColorChanged += OnColorPicked;
 
+        // Exodus: arm the eyedropper tool to copy a color from a decal on the map.
+        // Subscribe for the lifetime of this window instance (see Dispose); tying this to
+        // Opened/Close leaks a stale handler when the window is disposed without closing.
+        EyedropperButton.OnPressed += _ => _decalPlacementSystem.SetEyedropper(!_decalPlacementSystem.EyedropperActive);
+        _decalPlacementSystem.EyedropperPicked += OnEyedropperPicked;
+
         PickerOpen.OnPressed += _ =>
         {
             if (_picker is null)
@@ -120,6 +126,17 @@ private void OnColorPicked(Color color)
         RefreshList();
     }
 
+    // Exodus: apply a color copied from a decal via the eyedropper tool.
+    private void OnEyedropperPicked(Color color)
+    {
+        // Make sure the copied color is actually used when placing.
+        _useColor = true;
+        EnableColor.Pressed = true;
+
+        ColorPicker.Color = color;
+        OnColorPicked(color);
+    }
+
     private void UpdateDecalPlacementInfo()
     {
         if (_selected is null)
@@ -175,6 +192,16 @@ private void ButtonOnPressed(ButtonEventArgs obj)
         if (obj.Button.Name == null)
             return;
 
+        // Exodus: clicking the already-selected decal again clears the selection
+        // instead of leaving it stuck to the cursor.
+        if (obj.Button.Name == _selected)
+        {
+            _selected = null;
+            _decalPlacementSystem.ClearDecal();
+            RefreshList();
+            return;
+        }
+
         SelectDecal(obj.Button.Name);
     }
 
@@ -221,4 +248,12 @@ public override void Close()
         base.Close();
         _decalPlacementSystem.SetActive(false);
     }
+
+    // Exodus: drop the eyedropper subscription when this window instance is destroyed.
+    protected override void Dispose(bool disposing)
+    {
+        base.Dispose(disposing);
+        if (disposing)
+            _decalPlacementSystem.EyedropperPicked -= OnEyedropperPicked;
+    }
 }
diff --git a/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
new file mode 100644
index 00000000000..3281e382123
--- /dev/null
+++ b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
@@ -0,0 +1 @@
+decal-placer-window-eyedropper = Pick Color
diff --git a/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
new file mode 100644
index 00000000000..01c3bc45996
--- /dev/null
+++ b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
@@ -0,0 +1 @@
+decal-placer-window-eyedropper = Взять цвет

From f6862dacb074ee8e7270a94edc6571d230be3718 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Sat, 13 Jun 2026 23:16:44 +0300
Subject: [PATCH 2/7] delete 1 decal

---
 Content.Server/Decals/DecalSystem.cs | 53 ++++++++++++++++++++++------
 1 file changed, 42 insertions(+), 11 deletions(-)

diff --git a/Content.Server/Decals/DecalSystem.cs b/Content.Server/Decals/DecalSystem.cs
index 59ce4eedfc3..9dd3de5320d 100644
--- a/Content.Server/Decals/DecalSystem.cs
+++ b/Content.Server/Decals/DecalSystem.cs
@@ -266,22 +266,53 @@ private void OnDecalRemovalRequest(RequestDecalRemovalEvent ev, EntitySessionEve
             if (gridId == null)
                 return;
 
-            // remove all decals on the same tile
-            foreach (var (decalId, decal) in GetDecalsInRange(gridId.Value, ev.Coordinates.Position))
+            // Exodus-Start: remove only the topmost decal per click instead of wiping the whole tile.
+            // Original behaviour removed every decal in range:
+            // // remove all decals on the same tile
+            // foreach (var (decalId, decal) in GetDecalsInRange(gridId.Value, ev.Coordinates.Position))
+            // {
+            //     if (eventArgs.SenderSession.AttachedEntity != null)
+            //     {
+            //         _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
+            //             $"{ToPrettyString(eventArgs.SenderSession.AttachedEntity.Value):actor} removed a {decal.Color} {decal.Id} at {ev.Coordinates}");
+            //     }
+            //     else
+            //     {
+            //         _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
+            //             $"{eventArgs.SenderSession.Name} removed a {decal.Color} {decal.Id} at {ev.Coordinates}");
+            //     }
+            //
+            //     RemoveDecal(gridId.Value, decalId);
+            // }
+
+            // Pick the decal drawn on top (highest ZIndex, then highest id), matching what the user sees.
+            (uint Index, Decal Decal)? topmost = null;
+            foreach (var entry in GetDecalsInRange(gridId.Value, ev.Coordinates.Position))
             {
-                if (eventArgs.SenderSession.AttachedEntity != null)
+                if (topmost is not { } top
+                    || entry.Decal.ZIndex > top.Decal.ZIndex
+                    || (entry.Decal.ZIndex == top.Decal.ZIndex && entry.Index > top.Index))
                 {
-                    _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
-                        $"{ToPrettyString(eventArgs.SenderSession.AttachedEntity.Value):actor} removed a {decal.Color} {decal.Id} at {ev.Coordinates}");
-                }
-                else
-                {
-                    _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
-                        $"{eventArgs.SenderSession.Name} removed a {decal.Color} {decal.Id} at {ev.Coordinates}");
+                    topmost = entry;
                 }
+            }
 
-                RemoveDecal(gridId.Value, decalId);
+            if (topmost is not { } target)
+                return;
+
+            if (eventArgs.SenderSession.AttachedEntity != null)
+            {
+                _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
+                    $"{ToPrettyString(eventArgs.SenderSession.AttachedEntity.Value):actor} removed a {target.Decal.Color} {target.Decal.Id} at {ev.Coordinates}");
             }
+            else
+            {
+                _adminLogger.Add(LogType.CrayonDraw, LogImpact.High,
+                    $"{eventArgs.SenderSession.Name} removed a {target.Decal.Color} {target.Decal.Id} at {ev.Coordinates}");
+            }
+
+            RemoveDecal(gridId.Value, target.Index);
+            // Exodus-End
         }
 
         protected override void DirtyChunk(EntityUid uid, Vector2i chunkIndices, DecalChunk chunk)

From e355747aed57b1df10497719e0324de82cb41a08 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Sun, 14 Jun 2026 00:32:45 +0300
Subject: [PATCH 3/7] WIP. backup point. added copypaste.

---
 Content.Client/Decals/DecalPlacementSystem.cs | 161 +++++++++++++++---
 .../Decals/Overlays/DecalPlacementOverlay.cs  |  48 +++++-
 .../Decals/UI/DecalPlacerWindow.xaml.cs       |  30 ++++
 Content.Client/Input/ContentContexts.cs       |   4 +
 .../Options/UI/Tabs/KeyRebindTab.xaml.cs      |   4 +
 Content.Shared/Input/ContentKeyFunctions.cs   |   4 +
 .../en-US/_Exodus/decals/decal-window.ftl     |   3 +
 .../ru-RU/_Exodus/decals/decal-window.ftl     |   3 +
 Resources/keybinds.yml                        |   9 +
 9 files changed, 241 insertions(+), 25 deletions(-)

diff --git a/Content.Client/Decals/DecalPlacementSystem.cs b/Content.Client/Decals/DecalPlacementSystem.cs
index dfb4a16a4c7..2ca45792939 100644
--- a/Content.Client/Decals/DecalPlacementSystem.cs
+++ b/Content.Client/Decals/DecalPlacementSystem.cs
@@ -3,12 +3,14 @@
 using Content.Client.Decals.Overlays;
 using Content.Shared.Actions;
 using Content.Shared.Decals;
+using Content.Shared.Input; // Exodus
 using Robust.Client.GameObjects;
 using Robust.Client.Graphics;
 using Robust.Client.Input;
 using Robust.Shared.Input;
 using Robust.Shared.Input.Binding;
 using Robust.Shared.Map; // Exodus
+using Robust.Shared.Player; // Exodus
 using Robust.Shared.Prototypes;
 
 namespace Content.Client.Decals;
@@ -54,6 +56,23 @@ public void SetEyedropper(bool active)
     {
         _eyedropper = active && _active;
     }
+
+    // Сopy decal(s) under the cursor (hotkeys O / Ctrl+O), only while the window is open.
+    // Multi-decal "stamp": each entry is a decal plus its offset from the copied tile origin.
+    private readonly List<(Vector2 Offset, Decal Decal)> _stamp = new();
+    private bool _stamping;
+
+    /// <summary>
+    ///     Whether a multi-decal stamp is currently held and ready to be placed.
+    /// </summary>
+    public bool Stamping => _stamping && _stamp.Count > 0;
+
+    public IReadOnlyList<(Vector2 Offset, Decal Decal)> Stamp => _stamp;
+
+    /// <summary>
+    ///     Raised when a single decal is copied from the map, so the window can mirror its settings.
+    /// </summary>
+    public event Action<Decal>? DecalCopied;
     // Exodus-End
 
     public (DecalPrototype? Decal, bool Snap, Angle Angle, Color Color) GetActiveDecal()
@@ -81,6 +100,13 @@ public override void Initialize()
 
                     return true;
                 }
+
+                // Left click while a stamp is held places the whole copied stack.
+                if (_stamping)
+                {
+                    PlaceStamp(coords);
+                    return true;
+                }
                 // Exodus-End
 
                 if (!_active || _placing || _decalId == null)
@@ -118,12 +144,19 @@ public override void Initialize()
             .Bind(EngineKeyFunctions.EditorCancelPlace, new PointerStateInputCmdHandler(
             (session, coords, uid) =>
             {
-                // Exodus-Start: right click cancels the eyedropper instead of erasing.
+                // Exodus-Start: right click cancels the eyedropper or a held stamp instead of erasing.
                 if (_eyedropper)
                 {
                     _eyedropper = false;
                     return true;
                 }
+
+                if (_stamping)
+                {
+                    _stamping = false;
+                    _stamp.Clear();
+                    return true;
+                }
                 // Exodus-End
 
                 if (!_active || _erasing)
@@ -141,7 +174,12 @@ public override void Initialize()
                 _erasing = false;
 
                 return true;
-            }, true)).Register<DecalPlacementSystem>();
+            }, true))
+            // Exodus-Start: copy the decal (O) or the whole stack (Ctrl+O) under the cursor.
+            .Bind(ContentKeyFunctions.EditorCopyDecal, new PointerInputCmdHandler(OnCopyDecal))
+            .Bind(ContentKeyFunctions.EditorCopyDecalStack, new PointerInputCmdHandler(OnCopyDecalStack))
+            // Exodus-End
+            .Register<DecalPlacementSystem>();
 
         SubscribeLocalEvent<FillActionSlotEvent>(OnFillSlot);
         SubscribeLocalEvent<PlaceDecalActionEvent>(OnPlaceDecalAction);
@@ -239,35 +277,107 @@ public void ClearDecal()
     public void SetActive(bool active)
     {
         _active = active;
-        _eyedropper = false; // Exodus: arming is always an explicit user action.
+        // Exodus: arming/holding a tool is always an explicit user action.
+        _eyedropper = false;
+        _stamping = false;
+        _stamp.Clear();
         if (_active)
             _inputManager.Contexts.SetActiveContext("editor");
         else
             _inputSystem.SetEntityContextActive();
     }
 
-    // Exodus-Start: find the topmost decal under the given coordinates and return its color.
+    // Exodus-Start
+    /// <summary>"O": copy the topmost decal under the cursor into the placer.</summary>
+    private bool OnCopyDecal(ICommonSession? session, EntityCoordinates coords, EntityUid uid)
+    {
+        if (!_active)
+            return false;
+
+        _eyedropper = false;
+        _stamping = false;
+        _stamp.Clear();
+
+        if (TryGetDecalsUnder(coords, out _, out var decals) && Topmost(decals) is { } top)
+            DecalCopied?.Invoke(top.Decal);
+
+        return true;
+    }
+
+    /// <summary>"Ctrl+O": copy every decal under the cursor as a stamp to place as a group.</summary>
+    private bool OnCopyDecalStack(ICommonSession? session, EntityCoordinates coords, EntityUid uid)
+    {
+        if (!_active)
+            return false;
+
+        _eyedropper = false;
+        _stamp.Clear();
+        _stamping = false;
+
+        if (!TryGetDecalsUnder(coords, out var localPos, out var decals))
+            return true;
+
+        // Anchor offsets to the copied tile so the stamp stays tile-aligned when placed elsewhere.
+        var origin = localPos.Floored();
+        foreach (var (_, decal) in decals)
+            _stamp.Add((decal.Coordinates - origin, decal));
+
+        _stamping = true;
+        return true;
+    }
+
+    private void PlaceStamp(EntityCoordinates coords)
+    {
+        if (!TryGetGridLocal(coords, out var gridUid, out var localPos))
+            return;
+
+        var origin = localPos.Floored();
+        foreach (var (offset, decal) in _stamp)
+        {
+            var newPos = origin + offset;
+            var target = new EntityCoordinates(gridUid, newPos);
+            if (!target.IsValid(EntityManager))
+                continue;
+
+            var copy = new Decal(newPos, decal.Id, decal.Color, decal.Angle, decal.ZIndex, decal.Cleanable);
+            RaiseNetworkEvent(new RequestDecalPlacementEvent(copy, GetNetCoordinates(target)));
+        }
+    }
+
     private bool TryPickDecalColor(EntityCoordinates coords, out Color color)
     {
         color = Color.White;
+        if (!TryGetDecalsUnder(coords, out _, out var decals) || Topmost(decals) is not { } top)
+            return false;
 
+        color = top.Decal.Color ?? Color.White;
+        return true;
+    }
+
+    /// <summary>Resolve the grid and grid-local position under the given coordinates.</summary>
+    private bool TryGetGridLocal(EntityCoordinates coords, out EntityUid gridUid, out Vector2 localPos)
+    {
+        localPos = default;
         var mapPos = _transform.ToMapCoordinates(coords);
-        if (!_mapManager.TryFindGridAt(mapPos, out var gridUid, out _))
+        if (!_mapManager.TryFindGridAt(mapPos, out gridUid, out _))
             return false;
 
-        if (!TryComp<DecalGridComponent>(gridUid, out var decalGrid))
+        localPos = Vector2.Transform(mapPos.Position, _transform.GetInvWorldMatrix(gridUid));
+        return true;
+    }
+
+    /// <summary>Collect every decal whose 1x1 footprint contains the cursor.</summary>
+    private bool TryGetDecalsUnder(EntityCoordinates coords, out Vector2 localPos, out List<(uint Index, Decal Decal)> decals)
+    {
+        decals = new();
+        if (!TryGetGridLocal(coords, out var gridUid, out localPos)
+            || !TryComp<DecalGridComponent>(gridUid, out var decalGrid))
             return false;
 
-        var localPos = Vector2.Transform(mapPos.Position, _transform.GetInvWorldMatrix(gridUid));
         var chunkIndices = SharedDecalSystem.GetChunkIndices(localPos);
-
         if (!decalGrid.ChunkCollection.ChunkCollection.TryGetValue(chunkIndices, out var chunk))
             return false;
 
-        Decal? best = null;
-        var bestZ = int.MinValue;
-        var bestId = 0u;
-
         foreach (var (id, decal) in chunk.Decals)
         {
             // Decals are drawn as a 1x1 tile with their bottom-left corner at Coordinates.
@@ -275,20 +385,25 @@ private bool TryPickDecalColor(EntityCoordinates coords, out Color color)
                 localPos.Y < decal.Coordinates.Y || localPos.Y >= decal.Coordinates.Y + 1f)
                 continue;
 
-            // Match the overlay's draw order: highest ZIndex, then highest id, is on top.
-            if (best != null && (decal.ZIndex < bestZ || decal.ZIndex == bestZ && id < bestId))
-                continue;
-
-            best = decal;
-            bestZ = decal.ZIndex;
-            bestId = id;
+            decals.Add((id, decal));
         }
 
-        if (best == null)
-            return false;
+        return decals.Count > 0;
+    }
 
-        color = best.Color ?? Color.White;
-        return true;
+    /// <summary>Pick the decal drawn on top: highest ZIndex, then highest id (matches the overlay).</summary>
+    private static (uint Index, Decal Decal)? Topmost(List<(uint Index, Decal Decal)> decals)
+    {
+        (uint Index, Decal Decal)? best = null;
+        foreach (var entry in decals)
+        {
+            if (best is not { } b
+                || entry.Decal.ZIndex > b.Decal.ZIndex
+                || (entry.Decal.ZIndex == b.Decal.ZIndex && entry.Index > b.Index))
+                best = entry;
+        }
+
+        return best;
     }
     // Exodus-End
 }
diff --git a/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs b/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
index 40bd026ff91..16b88fd8da9 100644
--- a/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
+++ b/Content.Client/Decals/Overlays/DecalPlacementOverlay.cs
@@ -1,4 +1,5 @@
 using System.Numerics;
+using Content.Shared.Decals; // Exodus
 using Robust.Client.GameObjects;
 using Robust.Client.Graphics;
 using Robust.Client.Input;
@@ -13,6 +14,7 @@ public sealed partial class DecalPlacementOverlay : Overlay
     [Dependency] private IEyeManager _eyeManager = default!;
     [Dependency] private IInputManager _inputManager = default!;
     [Dependency] private IMapManager _mapManager = default!;
+    [Dependency] private IPrototypeManager _protoMan = default!; // Exodus
     private readonly DecalPlacementSystem _placement;
     private readonly SharedTransformSystem _transform;
     private readonly SpriteSystem _sprite;
@@ -30,12 +32,18 @@ public DecalPlacementOverlay(DecalPlacementSystem placement, SharedTransformSyst
 
     protected override void Draw(in OverlayDrawArgs args)
     {
-        // Exodus-Start: draw the eyedropper crosshair instead of a decal preview while picking a color.
+        // Exodus-Start: while a tool is active, draw its preview instead of the single-decal preview.
         if (_placement.EyedropperActive)
         {
             DrawEyedropper(args);
             return;
         }
+
+        if (_placement.Stamping)
+        {
+            DrawStamp(args);
+            return;
+        }
         // Exodus-End
 
         var (decal, snap, rotation, color) = _placement.GetActiveDecal();
@@ -76,7 +84,43 @@ protected override void Draw(in OverlayDrawArgs args)
         handle.SetTransform(Matrix3x2.Identity);
     }
 
-    // Exodus-Start: crosshair shown at the cursor marking the sample point of the eyedropper tool.
+    // Exodus-Start: preview of the copied decal stack, following the cursor before it is stamped.
+    private void DrawStamp(in OverlayDrawArgs args)
+    {
+        var mouseScreenPos = _inputManager.MouseScreenPosition;
+        var mousePos = _eyeManager.PixelToMap(mouseScreenPos);
+
+        if (mousePos.MapId != args.MapId)
+            return;
+
+        if (!_mapManager.TryFindGridAt(mousePos, out var gridUid, out _))
+            return;
+
+        var handle = args.WorldHandle;
+        handle.SetTransform(_transform.GetWorldMatrix(gridUid));
+
+        var localPos = Vector2.Transform(mousePos.Position, _transform.GetInvWorldMatrix(gridUid));
+        var origin = localPos.Floored();
+
+        foreach (var (offset, decal) in _placement.Stamp)
+        {
+            if (!_protoMan.TryIndex<DecalPrototype>(decal.Id, out var proto))
+                continue;
+
+            var texture = _sprite.Frame0(proto.Sprite);
+            var pos = origin + offset;
+            var color = decal.Color ?? Color.White;
+
+            if (decal.Angle == Angle.Zero)
+                handle.DrawTexture(texture, pos, color);
+            else
+                handle.DrawTexture(texture, pos, decal.Angle, color);
+        }
+
+        handle.SetTransform(Matrix3x2.Identity);
+    }
+
+    // crosshair shown at the cursor marking the sample point of the eyedropper tool.
     private void DrawEyedropper(in OverlayDrawArgs args)
     {
         var mouseScreenPos = _inputManager.MouseScreenPosition;
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
index 030775e8e42..e011d4ce3cc 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
@@ -58,6 +58,7 @@ public DecalPlacerWindow()
         // Opened/Close leaks a stale handler when the window is disposed without closing.
         EyedropperButton.OnPressed += _ => _decalPlacementSystem.SetEyedropper(!_decalPlacementSystem.EyedropperActive);
         _decalPlacementSystem.EyedropperPicked += OnEyedropperPicked;
+        _decalPlacementSystem.DecalCopied += OnDecalCopied; // Exodus: "O" copy hotkey
 
         PickerOpen.OnPressed += _ =>
         {
@@ -137,6 +138,32 @@ private void OnEyedropperPicked(Color color)
         OnColorPicked(color);
     }
 
+    // Exodus: mirror a decal copied from the map (hotkey "O") into the placer settings.
+    private void OnDecalCopied(Decal decal)
+    {
+        if (!_prototype.HasIndex<DecalPrototype>(decal.Id))
+            return;
+
+        _selected = decal.Id;
+
+        _useColor = decal.Color != null;
+        EnableColor.Pressed = _useColor;
+        _color = decal.Color ?? Color.White;
+        ColorPicker.Color = _color;
+
+        _rotation = (float) decal.Angle.Degrees;
+        RotationSpinBox.Value = _rotation;
+
+        _zIndex = decal.ZIndex;
+        ZIndexSpinBox.Value = _zIndex;
+
+        _cleanable = decal.Cleanable;
+        EnableCleanable.Pressed = _cleanable;
+
+        UpdateDecalPlacementInfo();
+        RefreshList();
+    }
+
     private void UpdateDecalPlacementInfo()
     {
         if (_selected is null)
@@ -254,6 +281,9 @@ protected override void Dispose(bool disposing)
     {
         base.Dispose(disposing);
         if (disposing)
+        {
             _decalPlacementSystem.EyedropperPicked -= OnEyedropperPicked;
+            _decalPlacementSystem.DecalCopied -= OnDecalCopied;
+        }
     }
 }
diff --git a/Content.Client/Input/ContentContexts.cs b/Content.Client/Input/ContentContexts.cs
index f9d3662f050..d7ec1268753 100644
--- a/Content.Client/Input/ContentContexts.cs
+++ b/Content.Client/Input/ContentContexts.cs
@@ -46,6 +46,10 @@ public static void SetupContexts(IInputContextContainer contexts)
             // Not in engine, because engine cannot check for sanbox/admin status before starting placement.
             common.AddFunction(ContentKeyFunctions.EditorCopyObject);
 
+            // Exodus: copy decal(s) under the cursor; only act while the decal spawn window is open.
+            common.AddFunction(ContentKeyFunctions.EditorCopyDecal);
+            common.AddFunction(ContentKeyFunctions.EditorCopyDecalStack);
+
             // Not in engine because the engine doesn't understand what a flipped object is
             common.AddFunction(ContentKeyFunctions.EditorFlipObject);
 
diff --git a/Content.Client/Options/UI/Tabs/KeyRebindTab.xaml.cs b/Content.Client/Options/UI/Tabs/KeyRebindTab.xaml.cs
index 1511da0f23c..e52530ffdfa 100644
--- a/Content.Client/Options/UI/Tabs/KeyRebindTab.xaml.cs
+++ b/Content.Client/Options/UI/Tabs/KeyRebindTab.xaml.cs
@@ -307,6 +307,10 @@ void AddCheckBox(string checkBoxName, bool currentState, Action<BaseButton.Butto
             AddButton(EngineKeyFunctions.EditorRotateObject);
             AddButton(ContentKeyFunctions.EditorFlipObject);
             AddButton(ContentKeyFunctions.EditorCopyObject);
+            // Exodus-Start
+            AddButton(ContentKeyFunctions.EditorCopyDecal);
+            AddButton(ContentKeyFunctions.EditorCopyDecalStack);
+            // Exodus-End
 
             AddHeader("ui-options-header-dev");
             AddButton(EngineKeyFunctions.ShowDebugConsole);
diff --git a/Content.Shared/Input/ContentKeyFunctions.cs b/Content.Shared/Input/ContentKeyFunctions.cs
index 0ddc086dfad..1d0883a7065 100644
--- a/Content.Shared/Input/ContentKeyFunctions.cs
+++ b/Content.Shared/Input/ContentKeyFunctions.cs
@@ -147,6 +147,10 @@ public static BoundKeyFunction[] GetHotbarBoundKeys() =>
         public static readonly BoundKeyFunction Vote8 = "Vote8";
         public static readonly BoundKeyFunction Vote9 = "Vote9";
         public static readonly BoundKeyFunction EditorCopyObject = "EditorCopyObject";
+        // Exodus-Start: copy decal(s) under the cursor in the decal placer
+        public static readonly BoundKeyFunction EditorCopyDecal = "EditorCopyDecal";
+        public static readonly BoundKeyFunction EditorCopyDecalStack = "EditorCopyDecalStack";
+        // Exodus-End
         public static readonly BoundKeyFunction EditorFlipObject = "EditorFlipObject";
         public static readonly BoundKeyFunction InspectEntity = "InspectEntity";
 
diff --git a/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
index 3281e382123..3a308522314 100644
--- a/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
+++ b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
@@ -1 +1,4 @@
 decal-placer-window-eyedropper = Pick Color
+
+ui-options-function-editor-copy-decal = Copy decal under cursor
+ui-options-function-editor-copy-decal-stack = Copy all decals under cursor
diff --git a/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
index 01c3bc45996..957be0e9666 100644
--- a/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
+++ b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
@@ -1 +1,4 @@
 decal-placer-window-eyedropper = Взять цвет
+
+ui-options-function-editor-copy-decal = Копировать декаль под курсором
+ui-options-function-editor-copy-decal-stack = Копировать все декали под курсором
diff --git a/Resources/keybinds.yml b/Resources/keybinds.yml
index 5c71546995e..2b934e44871 100644
--- a/Resources/keybinds.yml
+++ b/Resources/keybinds.yml
@@ -165,6 +165,15 @@ binds:
 - function: EditorCopyObject
   type: State
   key: P
+# Exodus-Start: copy decal under cursor (O) / copy whole decal stack (Ctrl+O)
+- function: EditorCopyDecal
+  type: State
+  key: O
+- function: EditorCopyDecalStack
+  type: State
+  key: O
+  mod1: Control
+# Exodus-End
 - function: SwapHands
   type: State
   key: X

From 5196b99181c3d00783f58aa3b42faf9f19953220 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Sun, 14 Jun 2026 01:17:13 +0300
Subject: [PATCH 4/7] WIP. backup point. fav added

---
 .../Decals/UI/DecalPlacerWindow.xaml          |  6 ++
 .../Decals/UI/DecalPlacerWindow.xaml.cs       | 37 +++++++++
 .../Decals/UI/PaletteColorPicker.xaml.cs      | 55 ++++++++++++--
 .../Decals/FavoriteDecalColorsSystem.cs       | 76 +++++++++++++++++++
 Content.Shared/_Exodus/CCVar/XCVars.cs        |  7 ++
 .../en-US/_Exodus/decals/decal-window.ftl     |  4 +
 .../ru-RU/_Exodus/decals/decal-window.ftl     |  4 +
 7 files changed, 184 insertions(+), 5 deletions(-)
 create mode 100644 Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs

diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
index f9e8c8b58be..107a7fe8f5a 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
@@ -12,6 +12,12 @@
 
         <BoxContainer Orientation="Vertical">
             <ColorSelectorSliders Name="ColorPicker" IsAlphaVisible="True" />
+            <!-- Exodus: toggle the current color as a favorite (★ = saved, ☆ = not saved) -->
+            <BoxContainer Orientation="Horizontal">
+                <Label Text="{Loc 'decal-placer-window-favorite-label'}" HorizontalExpand="True" />
+                <Button Name="FavoriteButton" Text="☆" MinWidth="40"
+                        ToolTip="{Loc 'decal-placer-window-favorite-tooltip'}" />
+            </BoxContainer>
             <Button Name="PickerOpen" Text="{Loc 'decal-placer-window-palette'}" />
             <!-- Exodus: eyedropper tool, copies the color of a decal already on the map -->
             <Button Name="EyedropperButton" Text="{Loc 'decal-placer-window-eyedropper'}" />
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
index e011d4ce3cc..ec60be94d05 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
@@ -1,4 +1,5 @@
 using System.Linq;
+using Content.Client._Exodus.Decals; // Exodus
 using Content.Client.Stylesheets;
 using Content.Shared.Decals;
 using Robust.Client.AutoGenerated;
@@ -19,6 +20,7 @@ public sealed partial class DecalPlacerWindow : DefaultWindow
     [Dependency] private IEntityManager _e = default!;
 
     private readonly DecalPlacementSystem _decalPlacementSystem;
+    private readonly FavoriteDecalColorsSystem _favorites; // Exodus
 
     public FloatSpinBox RotationSpinBox;
 
@@ -41,6 +43,7 @@ public DecalPlacerWindow()
         IoCManager.InjectDependencies(this);
 
         _decalPlacementSystem = _e.System<DecalPlacementSystem>();
+        _favorites = _e.System<FavoriteDecalColorsSystem>(); // Exodus
 
         // This needs to be done in C# so we can have custom stuff passed in the constructor
         // and thus have a proper step size
@@ -60,6 +63,15 @@ public DecalPlacerWindow()
         _decalPlacementSystem.EyedropperPicked += OnEyedropperPicked;
         _decalPlacementSystem.DecalCopied += OnDecalCopied; // Exodus: "O" copy hotkey
 
+        // Exodus: star toggles the current color in/out of favorites; keep it lit when the color matches.
+        FavoriteButton.OnPressed += _ =>
+        {
+            _favorites.Toggle(_color);
+            UpdateFavoriteStar();
+        };
+        _favorites.FavoritesChanged += UpdateFavoriteStar;
+        UpdateFavoriteStar();
+
         PickerOpen.OnPressed += _ =>
         {
             if (_picker is null)
@@ -125,11 +137,28 @@ private void OnColorPicked(Color color)
         _color = color;
         UpdateDecalPlacementInfo();
         RefreshList();
+        UpdateFavoriteStar(); // Exodus
+    }
+
+    // Exodus: reflect whether the current color is saved as a favorite (★ lit / ☆ unlit).
+    private void UpdateFavoriteStar()
+    {
+        // These run from a system event; a dead instance must not touch its controls (it would
+        // throw and abort the event's multicast before live windows run).
+        if (Disposed)
+            return;
+
+        var saved = _favorites.Contains(_color);
+        FavoriteButton.Text = saved ? "★" : "☆";
+        FavoriteButton.Modulate = saved ? Color.Gold : Color.White;
     }
 
     // Exodus: apply a color copied from a decal via the eyedropper tool.
     private void OnEyedropperPicked(Color color)
     {
+        if (Disposed)
+            return;
+
         // Make sure the copied color is actually used when placing.
         _useColor = true;
         EnableColor.Pressed = true;
@@ -141,6 +170,9 @@ private void OnEyedropperPicked(Color color)
     // Exodus: mirror a decal copied from the map (hotkey "O") into the placer settings.
     private void OnDecalCopied(Decal decal)
     {
+        if (Disposed)
+            return;
+
         if (!_prototype.HasIndex<DecalPrototype>(decal.Id))
             return;
 
@@ -162,6 +194,7 @@ private void OnDecalCopied(Decal decal)
 
         UpdateDecalPlacementInfo();
         RefreshList();
+        UpdateFavoriteStar();
     }
 
     private void UpdateDecalPlacementInfo()
@@ -284,6 +317,10 @@ protected override void Dispose(bool disposing)
         {
             _decalPlacementSystem.EyedropperPicked -= OnEyedropperPicked;
             _decalPlacementSystem.DecalCopied -= OnDecalCopied;
+            _favorites.FavoritesChanged -= UpdateFavoriteStar;
+            // Exodus: the palette picker is owned by this window; dispose it so its own
+            // FavoritesChanged subscription doesn't leak past this window's lifetime.
+            _picker?.Dispose();
         }
     }
 }
diff --git a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
index 8fc4cf2cbf5..adfa2736d40 100644
--- a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
+++ b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
@@ -1,4 +1,5 @@
-using Content.Shared.Decals;
+using Content.Client._Exodus.Decals; // Exodus
+using Content.Shared.Decals;
 using Robust.Client.AutoGenerated;
 using Robust.Client.Graphics;
 using Robust.Client.ResourceManagement;
@@ -13,14 +14,21 @@ public sealed partial class PaletteColorPicker : DefaultWindow
 {
     [Dependency] private IPrototypeManager _prototypeManager = default!;
     [Dependency] private IResourceCache _resourceCache = default!;
+    [Dependency] private IEntityManager _entManager = default!; // Exodus
 
     private readonly TextureResource _tex;
 
+    // Exodus: sentinel metadata marking the synthetic "Favorites" entry (not a prototype).
+    private static readonly object FavoritesMarker = new();
+    private readonly FavoriteDecalColorsSystem _favorites; // Exodus
+
     public PaletteColorPicker()
     {
         RobustXamlLoader.Load(this);
         IoCManager.InjectDependencies(this);
 
+        _favorites = _entManager.System<FavoriteDecalColorsSystem>(); // Exodus
+
         _tex = _resourceCache.GetResource<TextureResource>("/Textures/Interface/Nano/button.svg.96dpi.png");
 
         var i = 0;
@@ -33,6 +41,11 @@ public PaletteColorPicker()
             i += 1;
         }
 
+        // Exodus: append the user's favorites as a synthetic palette.
+        Palettes.AddItem(Loc.GetString("decal-placer-palette-favorites"));
+        Palettes.SetItemMetadata(i, FavoritesMarker);
+        _favorites.FavoritesChanged += OnFavoritesChanged;
+
         Palettes.OnItemSelected += args =>
         {
             Palettes.SelectId(args.Id);
@@ -46,11 +59,43 @@ public PaletteColorPicker()
     private void SetupList()
     {
         PaletteList.Clear();
-        foreach (var (color, value) in (Palettes.SelectedMetadata as ColorPalettePrototype)!.Colors)
+
+        // Exodus: the Favorites entry is dynamic, the rest are static prototypes.
+        if (Palettes.SelectedMetadata is ColorPalettePrototype palette)
         {
-            var item = PaletteList.AddItem(color, _tex.Texture);
-            item.Metadata = value;
-            item.IconModulate = value;
+            foreach (var (name, value) in palette.Colors)
+            {
+                var item = PaletteList.AddItem(name, _tex.Texture);
+                item.Metadata = value;
+                item.IconModulate = value;
+            }
         }
+        else
+        {
+            foreach (var color in _favorites.Colors)
+            {
+                var item = PaletteList.AddItem(color.ToHex(), _tex.Texture);
+                item.Metadata = color;
+                item.IconModulate = color;
+            }
+        }
+    }
+
+    // Exodus: refresh while the favorites palette is shown (e.g. the star added/removed a color).
+    private void OnFavoritesChanged()
+    {
+        // Runs from a system event; a dead instance must not touch its controls.
+        if (Disposed)
+            return;
+
+        if (Palettes.SelectedMetadata is not ColorPalettePrototype)
+            SetupList();
+    }
+
+    protected override void Dispose(bool disposing)
+    {
+        base.Dispose(disposing);
+        if (disposing) // Exodus
+            _favorites.FavoritesChanged -= OnFavoritesChanged;
     }
 }
diff --git a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
new file mode 100644
index 00000000000..16979f5d1a2
--- /dev/null
+++ b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
@@ -0,0 +1,76 @@
+using System.Linq;
+using Content.Shared._Exodus.CCVar;
+using Robust.Shared.Configuration;
+
+namespace Content.Client._Exodus.Decals;
+
+/// <summary>
+///     Stores the player's favorite decal colors locally. Persisted via an archived client-only
+///     cvar (<see cref="XCVars.DecalFavoriteColors"/>), so favorites survive relogs and restarts.
+/// </summary>
+public sealed class FavoriteDecalColorsSystem : EntitySystem
+{
+    [Dependency] private readonly IConfigurationManager _cfg = default!;
+
+    private readonly List<Color> _colors = new();
+
+    /// <summary>Raised whenever the favorites list changes, so open windows can refresh.</summary>
+    public event Action? FavoritesChanged;
+
+    public IReadOnlyList<Color> Colors => _colors;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+        Load();
+    }
+
+    public bool Contains(Color color)
+    {
+        var hex = color.ToHex();
+        return _colors.Any(c => c.ToHex() == hex);
+    }
+
+    /// <summary>Adds the color, or removes it if already a favorite. Returns true if it is now a favorite.</summary>
+    public bool Toggle(Color color)
+    {
+        if (Remove(color))
+            return false;
+
+        _colors.Add(color);
+        Save();
+        return true;
+    }
+
+    /// <summary>Removes the color if present. Returns true if something was removed.</summary>
+    public bool Remove(Color color)
+    {
+        var hex = color.ToHex();
+        var index = _colors.FindIndex(c => c.ToHex() == hex);
+        if (index < 0)
+            return false;
+
+        _colors.RemoveAt(index);
+        Save();
+        return true;
+    }
+
+    private void Load()
+    {
+        _colors.Clear();
+        var raw = _cfg.GetCVar(XCVars.DecalFavoriteColors);
+        foreach (var token in raw.Split(';', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
+        {
+            if (Color.TryFromHex(token) is { } color)
+                _colors.Add(color);
+        }
+    }
+
+    private void Save()
+    {
+        // Color.ToHex() already includes the leading '#', which TryFromHex requires when loading.
+        _cfg.SetCVar(XCVars.DecalFavoriteColors, string.Join(';', _colors.Select(c => c.ToHex())));
+        _cfg.SaveToFile();
+        FavoritesChanged?.Invoke();
+    }
+}
diff --git a/Content.Shared/_Exodus/CCVar/XCVars.cs b/Content.Shared/_Exodus/CCVar/XCVars.cs
index 2e548bddbf4..2c11e7804b5 100644
--- a/Content.Shared/_Exodus/CCVar/XCVars.cs
+++ b/Content.Shared/_Exodus/CCVar/XCVars.cs
@@ -15,4 +15,11 @@ public sealed partial class XCVars
 
     public static readonly CVarDef<string> WebAPIToken =
         CVarDef.Create("exds.webapi_token", "", CVar.SERVERONLY);
+
+    /// <summary>
+    /// User's favorite decal colors, stored as a ';'-separated list of hex colors.
+    /// Client-only and archived to client_config.toml so it survives relogs/restarts.
+    /// </summary>
+    public static readonly CVarDef<string> DecalFavoriteColors =
+        CVarDef.Create("exds.decal_favorite_colors", "", CVar.CLIENTONLY | CVar.ARCHIVE);
 }
diff --git a/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
index 3a308522314..bf7fe60392d 100644
--- a/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
+++ b/Resources/Locale/en-US/_Exodus/decals/decal-window.ftl
@@ -2,3 +2,7 @@ decal-placer-window-eyedropper = Pick Color
 
 ui-options-function-editor-copy-decal = Copy decal under cursor
 ui-options-function-editor-copy-decal-stack = Copy all decals under cursor
+
+decal-placer-window-favorite-label = Favorite color
+decal-placer-window-favorite-tooltip = Save the current color to the Favorites palette (click again to remove)
+decal-placer-palette-favorites = Favorites
diff --git a/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
index 957be0e9666..8a1bf0b1807 100644
--- a/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
+++ b/Resources/Locale/ru-RU/_Exodus/decals/decal-window.ftl
@@ -2,3 +2,7 @@ decal-placer-window-eyedropper = Взять цвет
 
 ui-options-function-editor-copy-decal = Копировать декаль под курсором
 ui-options-function-editor-copy-decal-stack = Копировать все декали под курсором
+
+decal-placer-window-favorite-label = Избранный цвет
+decal-placer-window-favorite-tooltip = Сохранить текущий цвет в палитру «Избранное» (повторный клик удаляет)
+decal-placer-palette-favorites = Избранное

From 4329e4bfac2f2470fb2786dd33ab6e33b804a61b Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Sun, 14 Jun 2026 01:43:36 +0300
Subject: [PATCH 5/7] comment fix, perf fix, basically - done

---
 Content.Client/Decals/DecalPlacementSystem.cs |  8 +++---
 .../Decals/UI/DecalPlacerWindow.xaml          |  3 ++-
 .../Decals/UI/DecalPlacerWindow.xaml.cs       | 27 +++++++++++--------
 .../Decals/UI/PaletteColorPicker.xaml.cs      | 15 +++++++----
 Content.Client/Input/ContentContexts.cs       |  3 ++-
 .../Decals/FavoriteDecalColorsSystem.cs       | 10 ++++---
 6 files changed, 41 insertions(+), 25 deletions(-)

diff --git a/Content.Client/Decals/DecalPlacementSystem.cs b/Content.Client/Decals/DecalPlacementSystem.cs
index 2ca45792939..5f63c4bf40f 100644
--- a/Content.Client/Decals/DecalPlacementSystem.cs
+++ b/Content.Client/Decals/DecalPlacementSystem.cs
@@ -57,7 +57,7 @@ public void SetEyedropper(bool active)
         _eyedropper = active && _active;
     }
 
-    // Сopy decal(s) under the cursor (hotkeys O / Ctrl+O), only while the window is open.
+    // Copy decal(s) under the cursor (hotkeys O / Ctrl+O), only while the window is open.
     // Multi-decal "stamp": each entry is a decal plus its offset from the copied tile origin.
     private readonly List<(Vector2 Offset, Decal Decal)> _stamp = new();
     private bool _stamping;
@@ -268,19 +268,21 @@ public void UpdateDecalInfo(string id, Color color, float rotation, bool snap, i
         _cleanable = cleanable;
     }
 
-    // Exodus: clear the active decal so it stops following the cursor when deselected.
+    // Exodus-Start: clear the active decal so it stops following the cursor when deselected.
     public void ClearDecal()
     {
         _decalId = null;
     }
+    // Exodus-End
 
     public void SetActive(bool active)
     {
         _active = active;
-        // Exodus: arming/holding a tool is always an explicit user action.
+        // Exodus-Start: arming/holding a tool is always an explicit user action.
         _eyedropper = false;
         _stamping = false;
         _stamp.Clear();
+        // Exodus-End
         if (_active)
             _inputManager.Contexts.SetActiveContext("editor");
         else
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
index 107a7fe8f5a..7362b533393 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml
@@ -12,12 +12,13 @@
 
         <BoxContainer Orientation="Vertical">
             <ColorSelectorSliders Name="ColorPicker" IsAlphaVisible="True" />
-            <!-- Exodus: toggle the current color as a favorite (★ = saved, ☆ = not saved) -->
+            <!-- Exodus-Start: toggle the current color as a favorite (★ = saved, ☆ = not saved) -->
             <BoxContainer Orientation="Horizontal">
                 <Label Text="{Loc 'decal-placer-window-favorite-label'}" HorizontalExpand="True" />
                 <Button Name="FavoriteButton" Text="☆" MinWidth="40"
                         ToolTip="{Loc 'decal-placer-window-favorite-tooltip'}" />
             </BoxContainer>
+            <!-- Exodus-End -->
             <Button Name="PickerOpen" Text="{Loc 'decal-placer-window-palette'}" />
             <!-- Exodus: eyedropper tool, copies the color of a decal already on the map -->
             <Button Name="EyedropperButton" Text="{Loc 'decal-placer-window-eyedropper'}" />
diff --git a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
index ec60be94d05..d526f300cc9 100644
--- a/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
+++ b/Content.Client/Decals/UI/DecalPlacerWindow.xaml.cs
@@ -56,14 +56,14 @@ public DecalPlacerWindow()
         Search.OnTextChanged += _ => RefreshList();
         ColorPicker.OnColorChanged += OnColorPicked;
 
-        // Exodus: arm the eyedropper tool to copy a color from a decal on the map.
-        // Subscribe for the lifetime of this window instance (see Dispose); tying this to
-        // Opened/Close leaks a stale handler when the window is disposed without closing.
+        // Exodus-Start
+        // Arm the eyedropper. Subscribe for this window instance's lifetime (unsubscribed in Dispose);
+        // tying it to Opened/Close leaks a stale handler when the window is disposed without closing.
         EyedropperButton.OnPressed += _ => _decalPlacementSystem.SetEyedropper(!_decalPlacementSystem.EyedropperActive);
         _decalPlacementSystem.EyedropperPicked += OnEyedropperPicked;
-        _decalPlacementSystem.DecalCopied += OnDecalCopied; // Exodus: "O" copy hotkey
+        _decalPlacementSystem.DecalCopied += OnDecalCopied; // "O" copy hotkey
 
-        // Exodus: star toggles the current color in/out of favorites; keep it lit when the color matches.
+        // Star toggles the current color in/out of favorites; keep it lit when the color matches.
         FavoriteButton.OnPressed += _ =>
         {
             _favorites.Toggle(_color);
@@ -71,6 +71,7 @@ public DecalPlacerWindow()
         };
         _favorites.FavoritesChanged += UpdateFavoriteStar;
         UpdateFavoriteStar();
+        // Exodus-End
 
         PickerOpen.OnPressed += _ =>
         {
@@ -140,7 +141,8 @@ private void OnColorPicked(Color color)
         UpdateFavoriteStar(); // Exodus
     }
 
-    // Exodus: reflect whether the current color is saved as a favorite (★ lit / ☆ unlit).
+    // Exodus-Start
+    // Reflect whether the current color is saved as a favorite (★ lit / ☆ unlit).
     private void UpdateFavoriteStar()
     {
         // These run from a system event; a dead instance must not touch its controls (it would
@@ -153,7 +155,7 @@ private void UpdateFavoriteStar()
         FavoriteButton.Modulate = saved ? Color.Gold : Color.White;
     }
 
-    // Exodus: apply a color copied from a decal via the eyedropper tool.
+    // Apply a color copied from a decal via the eyedropper tool.
     private void OnEyedropperPicked(Color color)
     {
         if (Disposed)
@@ -167,7 +169,7 @@ private void OnEyedropperPicked(Color color)
         OnColorPicked(color);
     }
 
-    // Exodus: mirror a decal copied from the map (hotkey "O") into the placer settings.
+    // Mirror a decal copied from the map (hotkey "O") into the placer settings.
     private void OnDecalCopied(Decal decal)
     {
         if (Disposed)
@@ -196,6 +198,7 @@ private void OnDecalCopied(Decal decal)
         RefreshList();
         UpdateFavoriteStar();
     }
+    // Exodus-End
 
     private void UpdateDecalPlacementInfo()
     {
@@ -252,7 +255,7 @@ private void ButtonOnPressed(ButtonEventArgs obj)
         if (obj.Button.Name == null)
             return;
 
-        // Exodus: clicking the already-selected decal again clears the selection
+        // Exodus-Start: clicking the already-selected decal again clears the selection
         // instead of leaving it stuck to the cursor.
         if (obj.Button.Name == _selected)
         {
@@ -261,6 +264,7 @@ private void ButtonOnPressed(ButtonEventArgs obj)
             RefreshList();
             return;
         }
+        // Exodus-End
 
         SelectDecal(obj.Button.Name);
     }
@@ -309,7 +313,7 @@ public override void Close()
         _decalPlacementSystem.SetActive(false);
     }
 
-    // Exodus: drop the eyedropper subscription when this window instance is destroyed.
+    // Exodus-Start: drop subscriptions and owned windows when this instance is destroyed.
     protected override void Dispose(bool disposing)
     {
         base.Dispose(disposing);
@@ -318,9 +322,10 @@ protected override void Dispose(bool disposing)
             _decalPlacementSystem.EyedropperPicked -= OnEyedropperPicked;
             _decalPlacementSystem.DecalCopied -= OnDecalCopied;
             _favorites.FavoritesChanged -= UpdateFavoriteStar;
-            // Exodus: the palette picker is owned by this window; dispose it so its own
+            // The palette picker is owned by this window; dispose it so its own
             // FavoritesChanged subscription doesn't leak past this window's lifetime.
             _picker?.Dispose();
         }
     }
+    // Exodus-End
 }
diff --git a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
index adfa2736d40..c4989aded36 100644
--- a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
+++ b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
@@ -18,9 +18,11 @@ public sealed partial class PaletteColorPicker : DefaultWindow
 
     private readonly TextureResource _tex;
 
-    // Exodus: sentinel metadata marking the synthetic "Favorites" entry (not a prototype).
+    // Exodus-Start
+    // Sentinel metadata marking the synthetic "Favorites" entry (not a prototype).
     private static readonly object FavoritesMarker = new();
-    private readonly FavoriteDecalColorsSystem _favorites; // Exodus
+    private readonly FavoriteDecalColorsSystem _favorites;
+    // Exodus-End
 
     public PaletteColorPicker()
     {
@@ -41,10 +43,11 @@ public PaletteColorPicker()
             i += 1;
         }
 
-        // Exodus: append the user's favorites as a synthetic palette.
+        // Exodus-Start: append the user's favorites as a synthetic palette.
         Palettes.AddItem(Loc.GetString("decal-placer-palette-favorites"));
         Palettes.SetItemMetadata(i, FavoritesMarker);
         _favorites.FavoritesChanged += OnFavoritesChanged;
+        // Exodus-End
 
         Palettes.OnItemSelected += args =>
         {
@@ -81,7 +84,8 @@ private void SetupList()
         }
     }
 
-    // Exodus: refresh while the favorites palette is shown (e.g. the star added/removed a color).
+    // Exodus-Start
+    // Refresh while the favorites palette is shown (e.g. the star added/removed a color).
     private void OnFavoritesChanged()
     {
         // Runs from a system event; a dead instance must not touch its controls.
@@ -95,7 +99,8 @@ private void OnFavoritesChanged()
     protected override void Dispose(bool disposing)
     {
         base.Dispose(disposing);
-        if (disposing) // Exodus
+        if (disposing)
             _favorites.FavoritesChanged -= OnFavoritesChanged;
     }
+    // Exodus-End
 }
diff --git a/Content.Client/Input/ContentContexts.cs b/Content.Client/Input/ContentContexts.cs
index d7ec1268753..ef1fe42b60c 100644
--- a/Content.Client/Input/ContentContexts.cs
+++ b/Content.Client/Input/ContentContexts.cs
@@ -46,9 +46,10 @@ public static void SetupContexts(IInputContextContainer contexts)
             // Not in engine, because engine cannot check for sanbox/admin status before starting placement.
             common.AddFunction(ContentKeyFunctions.EditorCopyObject);
 
-            // Exodus: copy decal(s) under the cursor; only act while the decal spawn window is open.
+            // Exodus-Start: copy decal(s) under the cursor; only act while the decal spawn window is open.
             common.AddFunction(ContentKeyFunctions.EditorCopyDecal);
             common.AddFunction(ContentKeyFunctions.EditorCopyDecalStack);
+            // Exodus-End
 
             // Not in engine because the engine doesn't understand what a flipped object is
             common.AddFunction(ContentKeyFunctions.EditorFlipObject);
diff --git a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
index 16979f5d1a2..873c6c9e01d 100644
--- a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
+++ b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
@@ -27,8 +27,7 @@ public override void Initialize()
 
     public bool Contains(Color color)
     {
-        var hex = color.ToHex();
-        return _colors.Any(c => c.ToHex() == hex);
+        return _colors.Any(c => SameColor(c, color));
     }
 
     /// <summary>Adds the color, or removes it if already a favorite. Returns true if it is now a favorite.</summary>
@@ -45,8 +44,7 @@ public bool Toggle(Color color)
     /// <summary>Removes the color if present. Returns true if something was removed.</summary>
     public bool Remove(Color color)
     {
-        var hex = color.ToHex();
-        var index = _colors.FindIndex(c => c.ToHex() == hex);
+        var index = _colors.FindIndex(c => SameColor(c, color));
         if (index < 0)
             return false;
 
@@ -55,6 +53,10 @@ public bool Remove(Color color)
         return true;
     }
 
+    // Compare at the 8-bit precision colors are stored/serialized at, without allocating hex strings.
+    private static bool SameColor(Color a, Color b)
+        => a.RByte == b.RByte && a.GByte == b.GByte && a.BByte == b.BByte && a.AByte == b.AByte;
+
     private void Load()
     {
         _colors.Clear();

From a6aa250b356c19aa253b654b2ae68dff2915e394 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Mon, 15 Jun 2026 01:29:57 +0300
Subject: [PATCH 6/7] ahem

---
 Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
index 873c6c9e01d..b05a7be8356 100644
--- a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
+++ b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
@@ -10,7 +10,7 @@ namespace Content.Client._Exodus.Decals;
 /// </summary>
 public sealed class FavoriteDecalColorsSystem : EntitySystem
 {
-    [Dependency] private readonly IConfigurationManager _cfg = default!;
+    [Dependency] private IConfigurationManager _cfg = default!;
 
     private readonly List<Color> _colors = new();
 

From 9a8ddaf3619613d971c168a639b41f8365446211 Mon Sep 17 00:00:00 2001
From: TryHardo7 <egor12340@mail.ru>
Date: Mon, 15 Jun 2026 21:36:41 +0300
Subject: [PATCH 7/7] leak fix

---
 Content.Client/Decals/DecalPlacementSystem.cs | 32 +++++++++++--------
 .../Decals/UI/PaletteColorPicker.xaml.cs      |  5 ++-
 Content.Client/Mapping/MappingScreen.xaml.cs  |  9 ++++++
 .../Decals/FavoriteDecalColorsSystem.cs       |  9 ++----
 Content.Server/Decals/DecalSystem.cs          |  2 +-
 5 files changed, 32 insertions(+), 25 deletions(-)

diff --git a/Content.Client/Decals/DecalPlacementSystem.cs b/Content.Client/Decals/DecalPlacementSystem.cs
index 5f63c4bf40f..441ae23b905 100644
--- a/Content.Client/Decals/DecalPlacementSystem.cs
+++ b/Content.Client/Decals/DecalPlacementSystem.cs
@@ -39,38 +39,44 @@ public sealed partial class DecalPlacementSystem : EntitySystem
     private bool _placing;
     private bool _erasing;
 
-    // Exodus-Start: eyedropper tool that copies the color of an existing decal on the map.
+    // Exodus-Start
     private bool _eyedropper;
 
     /// <summary>
-    ///     Whether the eyedropper (color picker) tool is currently selected.
+    /// Whether the eyedropper is currently selected.
     /// </summary>
     public bool EyedropperActive => _eyedropper;
 
     /// <summary>
-    ///     Raised when the eyedropper successfully copies a color from a decal on the map.
+    /// Raised when the eyedropper successfully copies a color from a decal.
     /// </summary>
     public event Action<Color>? EyedropperPicked;
 
     public void SetEyedropper(bool active)
     {
         _eyedropper = active && _active;
+
+        // The eyedropper and a paste (in copypaste mode) are mutually exclusive.
+        if (_eyedropper)
+        {
+            _stamping = false;
+            _stamp.Clear();
+        }
     }
 
-    // Copy decal(s) under the cursor (hotkeys O / Ctrl+O), only while the window is open.
-    // Multi-decal "stamp": each entry is a decal plus its offset from the copied tile origin.
+    // Copy decal(s) under the cursor, only while the window is open.
     private readonly List<(Vector2 Offset, Decal Decal)> _stamp = new();
     private bool _stamping;
 
     /// <summary>
-    ///     Whether a multi-decal stamp is currently held and ready to be placed.
+    /// Whether a multi-decal stamp is currently held and ready to be placed.
     /// </summary>
     public bool Stamping => _stamping && _stamp.Count > 0;
 
     public IReadOnlyList<(Vector2 Offset, Decal Decal)> Stamp => _stamp;
 
     /// <summary>
-    ///     Raised when a single decal is copied from the map, so the window can mirror its settings.
+    /// Raised when a single decal is copied from the map, so the window can mirror its settings.
     /// </summary>
     public event Action<Decal>? DecalCopied;
     // Exodus-End
@@ -90,7 +96,7 @@ public override void Initialize()
         CommandBinds.Builder.Bind(EngineKeyFunctions.EditorPlaceObject, new PointerStateInputCmdHandler(
             (session, coords, uid) =>
             {
-                // Exodus-Start: left click while the eyedropper is active copies a color instead of placing.
+                // Exodus-Start: left click while the eyedropper is active copies a color.
                 if (_eyedropper)
                 {
                     _eyedropper = false;
@@ -100,8 +106,6 @@ public override void Initialize()
 
                     return true;
                 }
-
-                // Left click while a stamp is held places the whole copied stack.
                 if (_stamping)
                 {
                     PlaceStamp(coords);
@@ -175,7 +179,7 @@ public override void Initialize()
 
                 return true;
             }, true))
-            // Exodus-Start: copy the decal (O) or the whole stack (Ctrl+O) under the cursor.
+            // Exodus-Start: copy the decal (O - not 0) or the whole stack (Ctrl+O) under the cursor.
             .Bind(ContentKeyFunctions.EditorCopyDecal, new PointerInputCmdHandler(OnCopyDecal))
             .Bind(ContentKeyFunctions.EditorCopyDecalStack, new PointerInputCmdHandler(OnCopyDecalStack))
             // Exodus-End
@@ -268,7 +272,7 @@ public void UpdateDecalInfo(string id, Color color, float rotation, bool snap, i
         _cleanable = cleanable;
     }
 
-    // Exodus-Start: clear the active decal so it stops following the cursor when deselected.
+    // Exodus-Start: clear the active decal. This wast here for years, really?!
     public void ClearDecal()
     {
         _decalId = null;
@@ -290,7 +294,7 @@ public void SetActive(bool active)
     }
 
     // Exodus-Start
-    /// <summary>"O": copy the topmost decal under the cursor into the placer.</summary>
+    /// <summary>"O": copy the top decal under the cursor into the placer.</summary>
     private bool OnCopyDecal(ICommonSession? session, EntityCoordinates coords, EntityUid uid)
     {
         if (!_active)
@@ -319,7 +323,7 @@ private bool OnCopyDecalStack(ICommonSession? session, EntityCoordinates coords,
         if (!TryGetDecalsUnder(coords, out var localPos, out var decals))
             return true;
 
-        // Anchor offsets to the copied tile so the stamp stays tile-aligned when placed elsewhere.
+        // So stamp stays tile-aligned when placed.
         var origin = localPos.Floored();
         foreach (var (_, decal) in decals)
             _stamp.Add((decal.Coordinates - origin, decal));
diff --git a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
index c4989aded36..6e69b35df3f 100644
--- a/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
+++ b/Content.Client/Decals/UI/PaletteColorPicker.xaml.cs
@@ -63,7 +63,7 @@ private void SetupList()
     {
         PaletteList.Clear();
 
-        // Exodus: the Favorites entry is dynamic, the rest are static prototypes.
+        // Exodus: the Favorites entry is dynamic.
         if (Palettes.SelectedMetadata is ColorPalettePrototype palette)
         {
             foreach (var (name, value) in palette.Colors)
@@ -85,10 +85,9 @@ private void SetupList()
     }
 
     // Exodus-Start
-    // Refresh while the favorites palette is shown (e.g. the star added/removed a color).
+    // Refresh while the favorites palette is shown.
     private void OnFavoritesChanged()
     {
-        // Runs from a system event; a dead instance must not touch its controls.
         if (Disposed)
             return;
 
diff --git a/Content.Client/Mapping/MappingScreen.xaml.cs b/Content.Client/Mapping/MappingScreen.xaml.cs
index 6ef9ce578bd..11f9c261ddd 100644
--- a/Content.Client/Mapping/MappingScreen.xaml.cs
+++ b/Content.Client/Mapping/MappingScreen.xaml.cs
@@ -209,4 +209,13 @@ public void UnPressActionsExcept(Control except)
         Pick.Pressed = Pick == except;
         Delete.Pressed = Delete == except;
     }
+
+    // Exodus-Start: Dispose palette picker explicitly so its FavoritesChanged subscription doesn't leak.
+    protected override void Dispose(bool disposing)
+    {
+        base.Dispose(disposing);
+        if (disposing)
+            _picker?.Dispose();
+    }
+    // Exodus-End
 }
diff --git a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
index b05a7be8356..d38b65c3a03 100644
--- a/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
+++ b/Content.Client/_Exodus/Decals/FavoriteDecalColorsSystem.cs
@@ -4,10 +4,6 @@
 
 namespace Content.Client._Exodus.Decals;
 
-/// <summary>
-///     Stores the player's favorite decal colors locally. Persisted via an archived client-only
-///     cvar (<see cref="XCVars.DecalFavoriteColors"/>), so favorites survive relogs and restarts.
-/// </summary>
 public sealed class FavoriteDecalColorsSystem : EntitySystem
 {
     [Dependency] private IConfigurationManager _cfg = default!;
@@ -30,7 +26,7 @@ public bool Contains(Color color)
         return _colors.Any(c => SameColor(c, color));
     }
 
-    /// <summary>Adds the color, or removes it if already a favorite. Returns true if it is now a favorite.</summary>
+    /// <summary>Adds the color, or removes it if already a favorite.</summary>
     public bool Toggle(Color color)
     {
         if (Remove(color))
@@ -42,7 +38,7 @@ public bool Toggle(Color color)
     }
 
     /// <summary>Removes the color if present. Returns true if something was removed.</summary>
-    public bool Remove(Color color)
+    private bool Remove(Color color)
     {
         var index = _colors.FindIndex(c => SameColor(c, color));
         if (index < 0)
@@ -70,7 +66,6 @@ private void Load()
 
     private void Save()
     {
-        // Color.ToHex() already includes the leading '#', which TryFromHex requires when loading.
         _cfg.SetCVar(XCVars.DecalFavoriteColors, string.Join(';', _colors.Select(c => c.ToHex())));
         _cfg.SaveToFile();
         FavoritesChanged?.Invoke();
diff --git a/Content.Server/Decals/DecalSystem.cs b/Content.Server/Decals/DecalSystem.cs
index 9dd3de5320d..92c97f27d7d 100644
--- a/Content.Server/Decals/DecalSystem.cs
+++ b/Content.Server/Decals/DecalSystem.cs
@@ -285,7 +285,7 @@ private void OnDecalRemovalRequest(RequestDecalRemovalEvent ev, EntitySessionEve
             //     RemoveDecal(gridId.Value, decalId);
             // }
 
-            // Pick the decal drawn on top (highest ZIndex, then highest id), matching what the user sees.
+            // Pick the decal on top (highest ZIndex, then highest id).
             (uint Index, Decal Decal)? topmost = null;
             foreach (var entry in GetDecalsInRange(gridId.Value, ev.Coordinates.Position))
             {