Have no idea what caused this but found a solution. Remove /usr/share/mozilla and /usr/bin/mozilla and reinstall Firefox. Backup your ~/.mozilla folder, probably it will work as it should when you put it back in the end.
Additional Info: - I have the "extensions" folder and "places.sqlite" syncing across computers and the others don't have this issue - after deleting ~/.mozilla, when Firefox restored its default profile, there was a bookmark (not always the same) from the toolbar of my deleted profile. And the icon would move around and then stop. Like the others before. As I see it, data from ".mozilla" on my home folder ended up in one (or both) of those folders in /usr and corrupted something. And I never executed Firefox as root so I can't see how that could have happened. -- Bookmark toolbar gets moving crazy on Firefox startup https://bugs.launchpad.net/bugs/590707 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