Comment 38 for bug 400088

It happens to me daily on my Ubuntu 10.04 system. I am running Firefox version 3.6.5pre but the problem has existed for me since at least ubuntu 9.10 and a few previous versions of Firefox. It doesn't happen every time, it seems to happen when Firefox has been left up for a while and multiple website have been visited, but then I guess the longer you have it up, the more chance you'll do the "thing" that causes it to hang on exit. Several times a day, when I exit Firefox, it doesn't terminate and when I check the Task Manager, it's using a lot of Processor and it never ends and as described before, you can't start another instance of Firefox until it's terminated/killed. I'm am not sure what the magic combination of things that causes it to not be able to be terminated. Also, it doesn't seem to be sucking processor prior to being terminated.