I want an option to ask for a confirmation when exiting moz. on win32 there is "quick launch" which does that, but on unix there is no way to prevent me from accidentally exiting moz by closing the last window.

Why do you want this ? Just restart mozilla...

found it.... see bug 57755 *** This bug has been marked as a duplicate of 39057 ***

restart doesn't cut it: I will have to re-enter the password and re-login to all the sites I was using. I will lose the browing history. In Emacs, C-x C-c asks for a confirmation. I want Mozilla to do the same.

this is a dupe, your request is indeed covered by that bug. you didn't ask for quick launch for linux (there's a bug for that), you asked for a confirmation dialog on exit. anyways, if you want quicklaunch, get yourself a good debugger (e.g. dbx), run mozilla in it. when you quit mozilla, you'll end up in the debugger, and you can instruct the debugger to run mozilla again. If you're using a good debugger (dbx) the libraries will still be loaded so mozilla will start quickly. please don't reopen bugs without taking the time to read the bug against which they are duped. *** This bug has been marked as a duplicate of 39057 ***