The current Release version of Mozilla Firefox or Firefox for short is for Windows 10 and 11 as there are no Firefox versions just for Windows 11. Firefox 135.0.1 from https://www.mozilla.org/firefox/all/ is for Windows 10 and 11 as you can see the minimum system requirements at https://www.mozilla.org/firefox/135.0.1/system-requirements/ which says "Windows 10 or later", the later being Windows 11. Firefox releases since 116.0 and later has required Windows 10, 11 to run. The Firefox UserAgent on Windows since Fx 116.0 only shows NT 10.0 whether you have Windows 10 or 11 for two reasons. To be more generic in fingerprinting and the actual reason is because Windows 11 is basically based on same NT 10.0 as Windows 10. https://en.wikipedia.org/wiki/Windows_NT#Releases