So you are saying you cannot install the Firefox 135.0.1 package from Mint http://packages.linuxmint.com/search.php?release=xia&section=any&keyword=firefox

The Firefox tarball from https://www.mozilla.org/firefox/all/desktop-release/ is basically just an archive as there is no package or installer or such. You just extract and run the firefox-bin to start Firefox is the basics. You can then create a launcher shortcut to the firefox-bin and use a Firefox icon from the /firefox/browser/chrome/icons/default/ folder. Btw the mention of chrome in this case has nothing to do with Google Chrome. Oh and make sure the firefox folder has read/write permissions for the user to get internal Firefox updates from Mozilla as a easy way if you are the only user is to have the firefox folder in /home

I'm sorry, but this was not my question.

Yes, I can install Firefox from LinuxMint-Repository (LinuxMint package manager) - no problem. This installs the LinuxMint version of Firefox. But I will avoid this installation option (this Firefox version!).

Instead of installing Firefox from LinuxMint as repository source, I want to add Mozilla release repository as an alternative package source in LinuxMint package manager. When entering the command "[sudo] apt-get install firefox", LinuxMint should use the Mozilla source for downloading, installung and later updating Firefox. I share the first installation option, the authors describs it their article. Therefore I followed their install instructions step by step.

My problem is: When entering the command "[sudo] apt-get install firefox", the LinuxMint version of Firefox will be installed allways. (But) The behaviour should be: checking, downlading and installing/updating Firefox from Mozilla release repository instead.

Your installation suggestion is one of the last suggestions in that article.

If you want to install the .deb version from packages.mozilla.org then you need to add that repository before you do the sudo apt-get install firefox

I just use the tarballs from Mozilla https://www.mozilla.org/firefox/all/ instead of any package builds. Downside they are not really installed so you have to set things up depending on your needs if starting Firefox from a launcher shortcut is is not enough.

Anyways you may get more help on say the linuxmint forum.

One reponse to this thread:

I opened a thread in LinuxMint Forum: https://forums.linuxmint.com/viewtopic.php?t=441238

One solution which helped, was: 1) Deinstallation of Firefox package completely. 2) Deleting folder "/usr/lib/firefox" completely (parts of it could still exists!). 3) After adding Mozilla as repository to package manager source list (descriped in the article "Installing Firefox on Linux"), cleaning apt cache with commands "apt autoremove" and "apt clean" before installing Firefox again.

@James: Can you forward this to the authors of the arcticle "Installing Firefox on Linux"?

This informations may help, if another Firefox version was installed before and change (afterwards) the way of the installation method.

I have my distro version. Then I run all Mozilla versions from my download folder. see screenshot