     @removePlaceholder()
 
   onDragEnd: (event) =>
+    return unless event.target.classList.contains('sortable')
+
     @clearDropTarget()
 
   onDragOver: (event) =>

      'tabs:split-left': => @splitTab('splitLeft')
      'tabs:split-right': => @splitTab('splitRight')

    @on 'dragstart', '.sortable', @onDragStart
    @on 'dragend', '.sortable', @onDragEnd
    @on 'dragleave', @onDragLeave
    @on 'dragover', @onDragOver
    @on 'drop', @onDrop

    @paneContainer = @pane.getContainer()
    @addTabForItem(item) for item in @pane.getItems()

    (@paneContainer.getPanes().length > 1) or (@pane.getItems().length > 1)

  onDragStart: (event) =>
    return unless event.target.classList.contains('sortable')

    event.originalEvent.dataTransfer.setData 'atom-event', 'true'

    element = $(event.target).closest('.sortable')
