I'm not expert in Apparmor but ...
Put Firefox in complain mode by running
Do your video chat which should now work.
sudo aa-complain /path/to/firefox
Run You'll now get a bunch of prompts. How you respond will depend on the nature of each prompt.
The final prompt will be to save changes. Agree to save the changes to the profile.
Then do another video chat.
Again run sudo aa-logprof. Again answer all prompts and save. Depending on the situation, you may have to repeat the process. Sometimes, choosing the "glob" alternative may be appropriate.
Finally, when aa-logprof has nothing further to suggest, you could put Firefox back into enforce mode by running
. Your videochat should then work even with the Firefox profile enforced.
sudo aa-enforce /path/to/firefox
BTW, it isn't necessary to turn off Apparmor altogether. Just put the suspect profile in complain mode to analyze the situation as I've tried to explain above.