This method is really simple for Chrome, Firefox and other OpenSSL apps: https://wiki.wireshark.org/TLS#using-the-pre-master-secret

You set an environment variable to instruct the app the write a file that Wireshark can use to decrypt its traffic, and change a setting in Wireshark to use that file, and that's it.

You will even be able to see decrypted WebRTC traffic.