WebRTC is a communication protocol that relies on JavaScript that can leak your actual IP address from behind your VPN, by default. This addon fixes that, making VPNs more effective [1].
[1] https://www.privacytools.io/webrtc.html
Source code is available here: https://github.com/ChrisAntaki/disable-webrtc-firefox
If there's an issue with the plugin, please let me know: https://github.com/ChrisAntaki/disable-webrtc-firefox/issues
Note: For a span of time, this plugin switched to using the newer `media.peerconnection.ice.default_address_only` setting. This setting claimed to secure WebRTC, without needing to disable it entirely. Some users pointed out the new setting actually doesn't block private IP address leaks for certain VPN configurations. After that I switched it back, not wanting to endanger anyone.