Removed square and improved UX

PixiEditor/Styles/DarkScrollBarStyle.xaml

@@ -13,6 +13,28 @@
     <SolidColorBrush x:Key="HorizontalNormalBrush" Color="#FF686868" />
     <SolidColorBrush x:Key="HorizontalNormalBorderBrush" Color="#888" />
 
+    <Style TargetType="{x:Type ScrollViewer}">
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="{x:Type ScrollViewer}">
+                    <Grid>
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition/>
+                            <ColumnDefinition Width="Auto"/>
+                        </Grid.ColumnDefinitions>
+                        <Grid.RowDefinitions>
+                            <RowDefinition/>
+                            <RowDefinition Height="Auto"/>
+                        </Grid.RowDefinitions>
+                        <ScrollContentPresenter Grid.Column="0" />
+                        <ScrollBar x:Name="PART_VerticalScrollBar" Grid.Row="0" Grid.Column="1" Value="{TemplateBinding VerticalOffset}" Maximum="{TemplateBinding ScrollableHeight}" ViewportSize="{TemplateBinding ViewportHeight}" Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}"/>
+                        <ScrollBar x:Name="PART_HorizontalScrollBar" Orientation="Horizontal" Grid.Row="1" Grid.Column="0" Value="{TemplateBinding HorizontalOffset}" Maximum="{TemplateBinding ScrollableWidth}" ViewportSize="{TemplateBinding ViewportWidth}" Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>
+                    </Grid>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+
     <LinearGradientBrush x:Key="ListBoxBackgroundBrush" StartPoint="0,0" EndPoint="1,0.001">
         <GradientBrush.GradientStops>
             <GradientStopCollection>

PixiEditor/ViewModels/SubViewModels/Main/LayersViewModel.cs

@@ -332,9 +332,10 @@ namespace PixiEditor.ViewModels.SubViewModels.Main
             {
                 return ((LayerGroupControl)parameter).GroupData;
             }
-            else if (parameter is Layer layer)
+            else if (parameter is Layer || parameter is LayerStructureItemContainer)
             {
-                var group = Owner.BitmapManager.ActiveDocument.LayerStructure.GetGroupByLayer(layer.LayerGuid);
+                Guid layerGuid = parameter is Layer layer ? layer.LayerGuid : ((LayerStructureItemContainer)parameter).Layer.LayerGuid;
+                var group = Owner.BitmapManager.ActiveDocument.LayerStructure.GetGroupByLayer(layerGuid);
                 if (group != null)
                 {
                     while (group.IsExpanded && group.Parent != null)