WebRTC seems to be broken

[Delphox]

System Details

• OS: Windows 10
• Thorium Version 138.0.7204.300

Problem
I first noticed when trying to join a Discord call, it was stuck in RTC connecting. Upon opening this test page, it gets multiple Connectivity and Network errors:

Here's the results for Thorium V130:

Additional Notes
Unfortunately downgrading Thorium with the same data causes issues so I'll have to use the Discord app for now. :(

[Alex313031]

@Delphox I wanna look into it. More serious bugs at hand right now and I have limited time. If I haven't responded in a few weeks tag me again or make another issue to get my attention. I'm trying to manage my work, the current release, and going through the long list of issues and triaging to try to fix important shit first. I'm one man, my fine sir. I hear you though, that's frustrating and video communication should "just work" in Thorium.

[Delphox]

No worries, thanks for responding, and take your time! 😊

[lunarock]

As a temporary fix, you can run Thorium with the following parameter:
--webrtc-ip-handling-policy=default

Another solution is to install the WebRTC Network Limiter or WebRTC Leak Prevent extension and set their settings to use default public and private IP addresses (as a WebRTC IP handling policy).

After this change, webrtc test page should no longer display errors:

[Delphox]

Thank you for the workaround! Just confirmed Discord calls are working again with the --webrtc-ip-handling-policy=default launch option.

[gz83]

@Alex313031

Although we have a temporary solution to this problem, I think kWebRTCIPHandlingDisableNonProxiedUdp is too strict. Perhaps we should consider changing it to kWebRTCIPHandlingDefaultPublicAndPrivateInterfaces?

This would use only the default HTTP route while also exposing the associated default private address.

Using DefaultPublicInterfaceOnly provides better privacy protection, but at the cost of potentially slower local network P2P connections (which would require TURN relay). And it will also affect the user experience.

Additionally, please see #1157

[Alex313031]

@Delphox Should be fixed in latest release: https://github.com/Alex313031/thorium/releases/tag/M138.0.7204.303