From Ubuntu 22.04 onwards Firefox is being packaged as a snap package. Existing Firefox installations get converted to a snap package which breaks certain extensions such as KeePassXC-Browser.
The new packages show as dummy transitional packages eg:
$ apt info firefox -a
Package: firefox
Version: 1:1snap1-0ubuntu2
Priority: optional
Section: web
Origin: Ubuntu
Maintainer: Ubuntu Mozilla Team <ubuntu-mozillateam@lists.ubuntu.com>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 261 kB
Provides: gnome-www-browser, iceweasel, www-browser, x-www-browser
Pre-Depends: debconf, snapd
Depends: debconf (>= 0.5) | debconf-2.0
Breaks: firefox-dbg (<< 1:1snap1), firefox-dev (<< 1:1snap1), firefox-geckodriver (<< 1:1snap1), firefox-mozsymbols (<< 1:1snap1)
Replaces: firefox-dbg (<< 1:1snap1), firefox-dev (<< 1:1snap1), firefox-geckodriver (<< 1:1snap1), firefox-mozsymbols (<< 1:1snap1)
Task: xubuntu-live, ubuntukylin-desktop
Download-Size: 72.3 kB
APT-Sources: http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
Description: Transitional package - firefox -> firefox snap
This is a transitional dummy package. It can safely be removed.
.
firefox is now replaced by the firefox snap.
The official Firefox Beta PPA includes packages for Ubuntu 22.04. These packages are not snap based.
sudo add-apt-repository ppa:mozillateam/firefox-next
sudo apt-get update
$ apt info firefox -a
Package: firefox
Version: 1:1snap1-0ubuntu2
Priority: optional
Section: web
Origin: Ubuntu
Maintainer: Ubuntu Mozilla Team <ubuntu-mozillateam@lists.ubuntu.com>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 261 kB
Provides: gnome-www-browser, iceweasel, www-browser, x-www-browser
Pre-Depends: debconf, snapd
Depends: debconf (>= 0.5) | debconf-2.0
Breaks: firefox-dbg (<< 1:1snap1), firefox-dev (<< 1:1snap1), firefox-geckodriver (<< 1:1snap1), firefox-mozsymbols (<< 1:1snap1)
Replaces: firefox-dbg (<< 1:1snap1), firefox-dev (<< 1:1snap1), firefox-geckodriver (<< 1:1snap1), firefox-mozsymbols (<< 1:1snap1)
Task: xubuntu-live, ubuntukylin-desktop
Download-Size: 72.3 kB
APT-Sources: http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
Description: Transitional package - firefox -> firefox snap
This is a transitional dummy package. It can safely be removed.
.
firefox is now replaced by the firefox snap.
Package: firefox
Version: 100.0~b3+build1-0ubuntu0.22.04.1
Priority: optional
Section: web
Maintainer: Ubuntu Mozilla Team <ubuntu-mozillateam@lists.ubuntu.com>
Installed-Size: 235 MB
Provides: gnome-www-browser, iceweasel, www-browser
Depends: lsb-release, libasound2 (>= 1.0.16), libatk1.0-0 (>= 1.12.4), libc6 (>= 2.35), libcairo-gobject2 (>= 1.10.0), libcairo2 (>= 1.10.0), libdbus-1-3 (>= 1.9.14), libdbus-glib-1-2 (>= 0.78), libfontconfig1 (>= 2.12.6), libfreetype6 (>= 2.10.1), libgcc-s1 (>= 4.0), libgdk-pixbuf-2.0-0 (>= 2.22.0), libglib2.0-0 (>= 2.42), libgtk-3-0 (>= 3.14), libharfbuzz0b (>= 0.6.0), libpango-1.0-0 (>= 1.14.0), libpangocairo-1.0-0 (>= 1.14.0), libstdc++6 (>= 12), libx11-6, libx11-xcb1 (>= 2:1.7.2), libxcb-shm0, libxcb1, libxcomposite1 (>= 1:0.4.5), libxcursor1 (>> 1.1.2), libxdamage1 (>= 1:1.1), libxext6, libxfixes3, libxi6, libxrandr2 (>= 2:1.4.0), libxrender1, libxtst6
Recommends: xul-ext-ubufox, libcanberra0, libdbusmenu-glib4, libdbusmenu-gtk3-4
Suggests: fonts-lyx
Replaces: kubuntu-firefox-installer
Xul-Appid: {ec8030f7-c20a-464f-9b0e-13a3a9e97384}
Download-Size: 63.5 MB
APT-Sources: https://ppa.launchpadcontent.net/mozillateam/firefox-next/ubuntu jammy/main amd64 Packages
Description: Safe and easy web browser from Mozilla
Firefox delivers safe, easy web browsing. A familiar user interface,
enhanced security features including protection from online identity theft,
and integrated search let you get the most out of the web.
sudo apt -y --purge remove firefox*
sudo snap remove firefox
/etc/apt/preferences.d/firefox with this content:Package: firefox*
Pin: origin ppa.launchpadcontent.net
Pin-Priority: 600
sudo apt -y install firefox firefox-locale-en