Also, there is the funny thing that when you updated to 22.04 and Firefox it's replaced by the snap version, you lose access to your previous Firefox account on the computer! The account isn't deleted... If you remove the snap version and install the normal version from a PPA, you get back your account with all the settings.
they seem to have fixed that at least. I had the same problem with a computer I updated immediately, but not with one that I waited a bit on. Incidentally you can fix this by copying your .mozilla directory in the correct place in the snap directory in your home folder
