This happens when you update the system or install new programs which are added to the menus. That may make it look unpredictable, since you don't always use the menus after downloading updates.
-- gnome-panel doesn't show all menu items https://launchpad.net/bugs/30146 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
