Fixing IsAutomaticCollapseEnabled

Author: batzen

Fluent.Ribbon/Controls/RibbonWindow.cs

@@ -245,9 +245,8 @@ private static void OnIsAutomaticCollapseEnabledChanged(DependencyObject d, Depe
 
     private void MaintainIsCollapsed()
     {
-        if (this.IsAutomaticCollapseEnabled == false)
+        if (this.IsAutomaticCollapseEnabled is false)
         {
-            this.ClearValue(IsCollapsedProperty);
             return;
         }
 
@@ -344,4 +343,4 @@ private void HandleIconMouseDown(object sender, MouseButtonEventArgs e)
     {
         return this.GetTemplateChild(name) as T;
     }
-}
+}