Read my comment again:
install Firefox from FlatPak
the Mozilla repo
or from source
In none of these cases will Ubuntu be able to install it from snap instead.
Only the Firefox “package” in the Ubuntu repos actually just links to a script that installs the snap.
8.10 was the last good Ubuntu. (It also had the best default wallpaper ever)
If you look at the “improvements” in every release since, you’ll notice that shit like they do currently isn’t an accident:
9.04 integrated web services into the main user interface.
9.10 integrated Ubuntu One (Ubuntu’s OneDrive, upgradable for money) by default and introduced the slooooow Ubuntu Software Center
10.04 integrated an interface to post on social media
10.10 added app purchases in the Software Center
11.04 made Unity the default
11.10 removed Gnome as fallback to Unity
12.04 introduced the buggy HUD
12.10 added the famous Amazon ad lense to it by default
and it goes on like this…