To install Firefox from Mozilla repo

The extrepo tool is used to manage external repositories in Debian. More about it at the end.

To install Firefox from Mozilla repo:

    sudo apt install extrepo

Make sure Firefox repo is available:

    extrepo search firefox

That should show it is listed in mozilla repo, so:

    sudo extrepo enable mozilla

Then update the package lists:

    sudo apt update

Check if Firefox is now available:

     apt list firefox

Then install Firefox:

    sudo apt install firefox

And presto, now you have the current version of Firefox and it will be updated whenever you do your regular system upgrades.

The new version pops up a wizard on first run which allows you to import bookmarks etc. from another version if you wish. It can live alongside firefox-esr and/or a downloaded bundle but you may delete them if you wish; by default they run separate profiles.

More about extrepo:

From the man page -

The extrepo tool is used to manage external repositories in Debian.  Before extrepo, users who wished to use software not packaged for Debian had to manually write the apt configuration files, run an unsigned script as root, or install an unsigned .deb package that contained all the configuration on        their system. None of these methods were very secure.

Extrepo remedies this by way of a metadata repository for external package repositories. The user can search the list of metadata repositories by way of "extrepo search", and manage them through "extrepo enable", "extrepo disable", or "extrepo update".

By default, only the main policy is enabled, which means only repositories with DFSG-free licensed packages are searched and can be enabled. This can be changed in the configuration file.

To show a concise list of repos available:

    $ extrepo search |grep Found

Description at Debian Packages - https://packages.debian.org/trixie/extrepo

An article explaining a few more aspects - https://linuxiac.com/how-to-use-extrepo-in-debian-to-manage-third-party-repositories/

This work was contributed by sunrat on Debian User Forums on 2025-11-04 21:22: https://forums.debian.net/viewtopic.php?t=164182