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Firefox is on the brink of being dropped by the US Government
(www.brycewray.com)
This is a most excellent place for technology news and articles.
Typical Firefox UA:
Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/120.0
Chrome:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36
See browsers started calling themselves "Mozilla" to say "Hey I can do what Firefox can!" (or back then still navigator, doesn't matter. So then sites started checking for "Gecko" (which is Mozilla's browser engine), and browsers (in this case Konqueror, I think) started adding "Hey, I'm like Gecko" to it. Then... it just goes on and on.
The only things not Mozilla in that Firefox UA are X11, Linux, and x86_64. It never stepped so low as to call itself "Mozilla (like Mosaic)".