I have encountered a crash when renaming a folder that has subfolders. The folder is under Local Folders, and has several subfolders. If I rename the folder e.g. 'Family' -> 'Family&Friends', it repositions farther down on the screen and the subfolders disappear. I then scroll down to locate it again. It's showing as open but nothing is visible below it. I click on the down-arrow icon to "close" it, then click on it again (now a right-arrow) to open it. At this point, it crashes. Good news is that the renaming worked just fine. It seems to be an in-memory confusion only.
Reporter: In the future, please include the BuildID in your bug reports. I saw no crash after following your steps on build 2001111503, Win98. But since I don't use Linux and noone else has confirmed, it is up to you to verify if this really a "worksforme". So, repeat exactly the steps to reproduce the bug, then report the results here. You may wish to try a more recent build: http://ftp.mozilla.org/pub/mozilla/nightly/latest/mozilla-win32-talkback.zip (as always, be sure to delete your old Mozilla directory before installing the new one) , particularly if your build is more than a month old (e.g. 20011117).
It doesn't happen for me now either after rebuilding with today's source (or with two downloads, one on Windows XP and the other Linux). Perhaps I just grabbed the source at a bad time; next time I'll confirm first with a downloaded build.
marking verified as worksforme based on reporter's last comment