In order to change your Firefox Configuration please do the following steps :

1. In the Location bar, type about:config and press Enter. The about:config "This might void your warranty!" warning page may appear.
2. Click I'll be careful, I promise! to continue to the about:config page.
3. browser.showQuitwarning needs to be set to true.

That doesn't work.

Once I set it to true, if I have one window open with multiple tabs, and try to exit, it comes up with a warning box, which I don't want.

Then if I check it to say 'don't show this again', the next time I run firefox the showQuitwarning setting has been set back to false. So then when I have multiple windows open and I file exit, all firefox shuts down with no warning.

-- The reason I want this is because I can *see* the tabs of the window I am in when I am clicking on file|exit, so visually, I'm not going to close anything that I didn't mean to close because it's right there visible to me at the top of the screen (the tabs are seen at the top of the screen) in the same area as where I am looking at and clicking File Exit.

But other firefox windows are not visible up there so it is easy to forget that they are open, since a lot of times I don't have any other windows open (if I *always* had other windows open then I would not forget them and be in more of a practice of checking the taskbar for them)

And this is all because I can't hit the red X in the top right corner without increasing the odds of hung firefox processes that don't truly exit (thus making me unable to start another session later without Ending Task which isn't good).

The hanging is daily but random and not reproducible, so it's very difficult to troubleshoot or fix.