gnome – Firefox has vanished from applications menu in Ubuntu 20.04

I use both Gnome and KDE Plasma on Ubuntu 20.04. I used the ‘Edit Application’ feature in Plasma to get Firefox to start using my dedicated graphics card. After this, I logged back into Gnome to see that Firefox has vanished from the Applications menu and the ‘Installed’ section in Software Centre. I can search for it in Software Centre and it says it’s still installed. I can even access and launch it from /usr/share/applications. I can still run it on KDE Plasma. But on Gnome it just won’t show up in the Applications menu despite uninstalling and reinstalling twice. I even undid what I had initially done on Plasma regarding the dedicated graphics card but that has not made any difference. Lastly, I tried to uninstall it on Gnome using Software Centre and then install it from Plasma using Discover, but it didn’t help either. The odd thing is that I did the same setting change regarding the dedicated GPU for three other applications and they’re all fine, but Firefox just won’t appear in the Applications menu. How do I fix this?