WebRTC allows a website directly detects your host machine’s true IP address, circumventing VPNs

Unfortunately for VPN users, WebRTC allows a website (or other WebRTC services) to directly detect your host machines true IP address, regardless of whether you are using a proxy server or VPN.

Interestingly, only Internet Explorer browser did not leak this info natively. Edge, Chrome, Firefox and Opera did. 

Testing for WebRTC IP Leakage

Visit Roseler's https://diafygi.github.io/webrtc-ips/ to see if an local IP appears.

https://ipleak.net/ is tool that detects whether your browser is vulnerable to a WebRTC leak.

How to Prevent WebRTC IP Leakage

Get uBlock Origin but you must configure to add the following; 

Or you can install Google's official Chrome extension WebRTC Network Limiter, but must be configured to use last option "Use my proxy server". 

uBlock Origin available for all browsers including Edge browser;