       @_prepareContentForDisplay()
 
   componentWillUnmount: =>
+    @_mounted = false
     unsubscribe() for unsubscribe in @_unsubscribers
     @command_unsubscriber.dispose()
 

    @MINIFY_THRESHOLD = 3

  componentDidMount: =>
    window.addEventListener("resize", @_onResize)
    @_unsubscribers = []
    @_unsubscribers.push MessageStore.listen @_onChange

    lastHeight = -1
    stableCount = 0
    scrollIfSettled = =>
      return unless @_mounted
      messageWrapHeight = messageWrap.getBoundingClientRect().height
      if messageWrapHeight isnt lastHeight
        lastHeight = messageWrapHeight
