   initialize: (@pane) ->
     @on 'dragstart', '.sortable', @onDragStart
     @on 'dragend', '.sortable', @onDragEnd
+    @on 'dragleave', @onDragLeave
     @on 'dragover', @onDragOver
     @on 'drop', @onDrop
 

      sortables.index(el.next('.sortable'))
    else
      sortables.index(el) + 1


    @find(".is-dragging").removeClass 'is-dragging'
    @removeDropTargetClasses()
    @removePlaceholderElement()

    event.stopPropagation()

