Upgrading Ubuntu 16.04 to 18.04 and then to 20.04, and using Unity Desktop, the Menubar is missing
This question is Ubuntu 20.04 Specific.
After Upgrading from Ubuntu 16.04 via 18.04 to 20.04, my menu bar is missing. I have used sudo do-release-upgrade -d -f DistUpgradeViewGtk3 to upgrade, and then used sudo dpkg-reconfigure lightdm to make lightdm my display manager. My File Manager, Firefox and Chromium didn't have the menus (like File, Edit, View, ..., Help). But My Konsole and Gnome Terminal have these menus.
After removing cheese with sudo apt-get remove --auto-remove cheese I got back the menu of Chromium browser back. File manager and Firefox still does not have the menu.
How to bring back the menu bar in Firefox, in Unity?