I'm seeing something slightly different to what you're describing in a xenial VM: submenus do open empty indeed, however after a fraction of a second they are redrawn with the correct menu entries.
Can you confirm that in your case you need to close the menu and re-open it again to make its content appear? ** Summary changed: - Menus aren't populated first time + Unity menus aren't initially populated ** Changed in: firefox (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1854753 Title: Unity menus aren't initially populated To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1854753/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs