It really can’t. If you spoof the user agent it’ll crash immediately after a call starts.

I suspect they use something extra on top of normal WebRTC.

Well they are just lying, it works fine with Firefox and has worked fine for years. I live in the EU though. Sucks to be american these days, I guess?

This is not mildly infuriating this is the free internet being eroded through Google’s control of Chrome

Try changing your user agent to a Chrome one (e.g. Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36). Works a treat!

This is likely legacy code. Firefox used to have a lot of issues with WebRTC, so practically all video conferencing systems blocked it. Teams probably has some “block Firefox because it doesn’t work properly” check that was written 5+ years ago and none of the current developers are even aware of its existence.

Well-coded ones did feature detection instead of checking the user-agent, meaning they automatically started allowing Firefox as soon as it implemented all the required features.

Feature detection is usually the way to go. If your website / webapp depends on a particular feature, check if that specific feature exists, rather than checking for particular browsers. Browser checks are still needed in some cases, for example Safari sometimes reports that it supports particular features but it really doesn’t (or they’re so buggy to the point where they’re unusable), but that’s relatively rare.

This team block is so agressive to firefox users that it’s literaly hardcoded as if web browser firefox then deny.

You cam override that by changing a parameter in firefox to advertise itself as another we browser. I don’t remeber how i did it but, once i had to use firefox and i just changed that stting in order to advertise me to the host as a edge browser. With that changed i could use teams as normal.

Epic drm.