Do you have a specific / concrete example in mind? Or are you mistaking a feature from something other than a mainstream browser?

IIRC it defaults to a Windows user agent even when you use it on other operating systems.

https://github.com/mozilla-firefox/firefox/commit/eb2f90f870...

This OS spoofing behavior was added in 2019-01-09 with this commit:

https://github.com/mozilla-firefox/firefox/commit/264fe08c09...

So Firefox has spoofed the User-Agent as a Windows machine on Linux for around 6 years, and only stopped doing it early this year. Would love to see whatever gaslit you into forgetting this easy to test and validate behavior.

This was part of the resist fingerprinting feature. Which is an advanced user configuration. I can alter the user agent directly myself too.

Sigh

I regret getting tricked into arguing over such a pedantic specific, So I'd like to redirect the actual point, which is that it's not meaningful if a Firefox browser pretends to be a slightly different Firefox browser, but instead the problem is when something that's not a browser, claims to be and behave like one.

Still, +1 for finding the commit, I'd forgotten about this feature. I thought only the tor browser was this foolish.