Ubuntu环境下打开Firefox报错: Firefox is already running, but is not responding.

在ubuntu下启动firefox可能会报错 Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

解决办法：在终端输入killall firefox

在该命令杀死firefox所有进程后，再点开firefox就可以正常启动了。