Ubuntu 22.04 comes with Ubuntu-Software which is snap store and Firefox comes as a snap package. If you don't like this set up you can remove all installed snap packages including Firefox and install gnome-software with flatpak plugin, add flatpak repo and install Firefox Flatpak version.
$ sudo snap remove --purge firefox
$ sudo snap remove --purge snap-store
$ sudo snap remove --purge gnome-3-38-2004
$ sudo snap remove --purge gtk-common-themes
$ sudo snap remove --purge snapd-desktop-integration
$ sudo snap remove --purge bare
$ sudo snap remove --purge core20
$ sudo snap remove --purge snapd
$ sudo gedit /etc/apt/preferences.d/nosnap.pref
Paste the following:
# To prevent repository packages from triggering the installation of snap,
# this file forbids snapd from being installed by APT.
Package: snapd
Pin: release a=*
Pin-Priority: -10
Save and refresh package cache
$ sudo apt update
$ sudo apt install gnome-software
$ sudo apt remove --purge gnome-software-plugin-snap
$ sudo apt install gnome-software-plugin-flatpak
$ flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
Restart
Open gnome-software and install Firefox