Re: “Localhost tracking” explained. It could cost Meta 32 billion.

VanguardLH, 2025-06-14 08:03:

[...]

So, we're back to how WebRTC can be abused to identify you.  While the
desktop web browsers let you disable WebRTC through settings, the
deliberately crippled mobile web browsers do not.  Alas, even the
desktop web browsers are taking away the option to disable WebRTC, so
you need an add-on for them, too.
 
You can test by visiting:
 
https://webbrowsertools.com/test-webrtc-leak/

False positive.

It reports "N/A" for my private IP address and still says "Your browser
is leaking webrtc ip-address!". My *public* IP address is not a secret,
when I visit a website.

https://ipleak.net/
(look under "Your IP addresses - WebRTC detection")

Same - just showing my public address which is not a secret anyway.

Be aware that disabling the WebRTC API can break some web sites.

Yes - especially those which offer video calls and live video streaming
using WebRTC. HLS ist not really suitable for video calls.

[...]

Even if using a VPN, WebRTC could still expose your IP addresses, so you
should test and a leak test site while using your VPN.

I did - both testsites above did *not* show my private IP address. And
no, I did not disable WebRTC.


--
Arno Welzel
https://arnowelzel.de