I'm having problems broadcasting and subscribing with WebRTC while using Firefox. Sometimes it does not connect, and when it does, the image quality can be bad.
There are unique issues to each browser and the way they implement the protocol.
This link shows the most recent bugs with Firefox and WebRTC. You may be able to find your particular issue here. Take a look at what has been reported, and decide whether you should report your issue.
See also our guide on client-side troubleshooting.
Lastly, if the issue is a camera access failure, see Why am I experiencing camera access failures in the browser?
Revised 11/10/2020 MD