       #TODO Remove once old events are no longer supported
       @item.on('title-changed', titleChangedHandler)
       @titleSubscription = dispose: =>
-        @item.off('title-changed', titleChangedHandler)
+        @item.off?('title-changed', titleChangedHandler)
 
     iconChangedHandler = =>
       @updateIcon()

      #TODO Remove once old events are no longer supported
      @item.on('icon-changed', iconChangedHandler)
      @iconSubscription = dispose: =>
        @item.off('icon-changed', iconChangedHandler)

    modifiedHandler = =>
      @updateModifiedStatus()

      #TODO Remove once old events are no longer supported
      @item.on('modified-status-changed', modifiedHandler)
      @modifiedSubscription = dispose: =>
        @item.off?('modified-status-changed', modifiedHandler)

    @configSubscription = atom.config.observe 'tabs.showIcons', =>
      @updateIconVisibility()
