Honestly no, I have a bunch of extensions but I never took specific action to make teams work. You do have to make sure popup are allowed and ublock and similar tools don’t interfere with it, but it worked for me.
You might try grabbing a portable Firefox install from Portable Apps and testing that.
I don’t know what’s up with your setup, but this is untrue. I’ve used Firefox for teams in browser for years with no issues.
I can try again with a friend on Momday. Is there a specific user agent extension or a about:config option you used?
Honestly no, I have a bunch of extensions but I never took specific action to make teams work. You do have to make sure popup are allowed and ublock and similar tools don’t interfere with it, but it worked for me.
You might try grabbing a portable Firefox install from Portable Apps and testing that.