Fixed not being able to draw on folder mask

src/PixiEditor/ViewModels/Tools/ToolViewModel.cs

@@ -120,7 +120,7 @@ internal abstract class ToolViewModel : ObservableObject, IToolHandler
 
         foreach (var type in SupportedLayerTypes)
         {
-            if (type.IsInstanceOfType(layer))
+            if (type.IsInstanceOfType(layer) || IsFolderAndRasterSupported(layer))
             {
                 CanBeUsedOnActiveLayer = true;
                 return;
@@ -129,6 +129,11 @@ internal abstract class ToolViewModel : ObservableObject, IToolHandler
 
         CanBeUsedOnActiveLayer = false;
     }
+    
+    private bool IsFolderAndRasterSupported(IStructureMemberHandler layer)
+    {
+        return SupportedLayerTypes.Contains(typeof(IRasterLayerHandler)) && layer is IFolderHandler;
+    }
 
     private void OnLanguageChanged(Language obj)
     {