What's so unbelievable about faking something to get an app that works perfectly fine on your browser to stop refusing to work on your browser?

I think he's talking about the fact that they had to do that at all.

In that case, what's unbelievable about a developer phoning feature detection in and just using the user-agent string? :P

Is it possible to detect the format of the webrtc video? That sounds difficult anyway.

Blame slack.

This.