     @clearDropTarget()
 
   onDragOver: (event) ->
+    return unless isAtomTabEvent(event)
+    return unless itemIsAllowed(event, @location)
+
     event.preventDefault()
-    unless isAtomTabEvent(event)
-      event.stopPropagation()
-      return
-
-    return unless itemIsAllowed(event, @location)
+    event.stopPropagation()
 
     newDropTargetIndex = @getDropTargetIndex(event)
     return unless newDropTargetIndex?

  onPaneDragLeave: (event) ->
    return unless isAtomTabEvent(event)
    return if @pane.getItems().length > 1 or atom.config.get('tabs.alwaysShowTabBar')
    unless @paneElement.contains(event.relatedTarget)
      @element.classList.add('hidden')


  onPaneDragEnter: (event) ->
    return unless isAtomTabEvent(event)
    return if @pane.getItems().length > 1 or atom.config.get('tabs.alwaysShowTabBar')
    return unless itemIsAllowed(event, @location)
    if @paneElement.contains(event.relatedTarget)
      @element.classList.remove('hidden')

