Every guide, comparison and detector run we have published under proxy.
A WebRTC leak test shows a local IP, a public IP and an SDP log, and only one comparison on that page actually decides whether you leak. What each field means, why a random .local address is not a leak, and the IPv6 case most people miss.
WebRTC gathers ICE candidates over UDP, outside the HTTP or SOCKS proxy path, so a site can read your real public IP with two lines of JavaScript regardless of what the address bar shows. Disabling WebRTC outright trades one tell for another.