The problem occurs constantly. Crash report here: https://crash-stats.mozilla.com/report/index/fc9598bb-64de-431a-848f-1fcd32110506 I'm surprised to see many "possible duplicates" that have been fixed years ago.

> The problem occurs constantly. The stack you link to is showing a crash inside your Linux system libraries due to an X11Error (libbonoboui, etc). The "possible duplicates" are just any crashes with the same top frame, which means anything crashing due to an X11Error. What exact versions of XOrg and libbonoboui are you using? Anything else interesting about your setup X or GTK wise?

Sorry Boris, I should have been more specific: "The problem occurs constantly on my machine", I'm pretty sure it's not the case for everyone else out there. I should have also linked the possible duplicates I was referring to: #17584 (reported for Windows) and #63235 The versions reported by my packet manager are: xorg: 1:7.6+4ubuntu3 libbonoboui2-0: 2.24.5-0ubuntu1 I never tweak my X or GTK setup manually. Let me know if I can provide any other helpful info. Regards, Louis-Rémi

Karl, any ideas?

After some test, additional info: the bug only appears when I use Ubuntu with Unity and when Firebug is enabled at the same time. If I switch back to Ubuntu Classic and leave Firebug enabled, the problem disappear. If I disable Firebug and keep using Unity, the problem disappear. I was using Firebug 1.7.1b2, then upgraded to 1.8.0a2 and downgraded to 1.7.0, but it didn't help.

I wouldn't have thought that a shutdown crash would prevent a dog from eating its food, but this should be fixed in 4.0.1.