Firefox not responding

End Firefox processes

If Firefox did not shut down normally when you last used it, Firefox might still be running in the background, even though it is not visible. Or Firefox think he is running but in fact no, because of several reboot for exemple.

Check that Firefox is really not running

Open a terminal and run :

$ ps x | grep fire

If firefox is running you should obtain a line like :

32107 ?        Sl    33:45 /usr/lib/firefox/firefox

It means that firefox is really running.

You can kill it softly with :

$ kill -1 "PID NUMBER" 

Or hardly with :

$ kill -9 "PID NUMBER" 

If you don’t find this line, you ca go to the next step.

Remove the profile lock file

If ending the Firefox processes didn’t help, it may be that Firefox previously exited without deleting the lock file.

Go to your Firefox profile folder.

$ cd ~/.mozilla/firefox/

You should find inside :

Crash Reports

Your profile is the folder with the numbers and letters here ‘h9q738j2.default’ go inside and remove files lock and .parentlock.

So in this exemple :

$ cd ~/.mozilla/firefox/h9q738j2.default
$ rm lock .parentlock