So is it the "Some devices are running Firefox versions which have reached their end-of-support. Support and services are no longer available for these versions ..." that you are being confused by in thinking the current Firefox 120.0.1 Release (November 30, 2023) and Firefox in general is now retired?. Nothing in your screenshot says Firefox 121.0.1 is EOS or EOL.

The (desktop) Firefox web browser for Windows, macOS, and Linux is one of Mozilla's main products and is most certainly not retired.

Here is the calendar of the upcoming milestones of Firefox https://whattrainisitnow.com/calendar/monthly/ (as you can see, still very active) https://whattrainisitnow.com/

Fx 121.0 is being planned for Release on December 19 along with Fx 115.6.0esr. At this point the previous Release Fx 121.0.1 with be End of Life or EOL as been the case with previous releases since.

Mozilla has ended support for older EOL OS's over the years with (desktop) Firefox. This may be what the ""Some devices are running Firefox versions which have reached their end-of-support ..." message was referring to.

For example the latest to support Windows XP and Vista was Firefox 52.9.0esr https://support.mozilla.org/en-US/kb/end-support-windows-xp-and-vista

For macOS 10.9-10.11 users the latest version was Fx 78.15.0esr https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr

At present for Windows 7, 8, 8.1 and macOS 10.12, 10.13, 10.14 users the latest version is the Fx 115 ESR (still supported) which is currently at Fx 115.5.0esr as Fx 116.0 and later requires Windows 10 or later and macOS 10.15 or later. https://support.mozilla.org/en-US/kb/firefox-users-windows-7-8-and-81-moving-extended-support https://support.mozilla.org/en-US/kb/firefox-users-macos-1012-1013-1014-moving-to-extended-support

Hi James,

Thank you for your reply. Here you have the Firefox version distribution for our devices. The screenshot shows that 297 devices have Firefox 120.0.1. Check the column on the let side. It does say EOS . That also shows on all other versions we have and that is what is confusing me.

Thank you, Suzane

For some reason it says 120.0.1.0 when no such version exists as that could be a the reason or not.

The current version is 120.0.1 as you can download it as the current Release on *.mozilla.org including www.mozilla.org/firefox/all/

Also the 119.0.1.0 and 119.0.0.0 does not exist as you can see on https://www.mozilla.org/firefox/releases/

For Releases the second number normally stays at zero while the third updates by one if there is a update for security and or stability that could not wait till next major Release. There has not be a fourth number in use since the days of Firefox 1.5 and 2.0 Release channel builds. Any versions that has second number updates is usually the ESR channel builds. ESR short for Extended Support Release.

Hi James. That is how Microsoft displays the version. The devices do have version 12.0.1 . See attachment for details.

Regards, Suzane