I tried JohnBender's suggestion, and noticed that a bunch of files were owned by root. Is there any reason they should be owned by root? On a whim, I found that the following solved all the problems described above:
sudo chown -R myusername.myusername .mozilla/firefox -- Firefox 3 bookmarks lost after unclean shutdown https://bugs.launchpad.net/bugs/241609 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs