Can not link desktop on v6-only, or NAT64 network

[mcr]

• [ X] I have searched open and closed issues for duplicates

• I am using Signal-Desktop as provided by the Signal team, not a 3rd-party package.

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Bug Description

New laptop, installed signal-desktop from apt repo on Ubuntu20 LTS.
I was unable to get a QR code while on an IPv6, NAT64 network. (specifically, IETF-NAT64 network at IETF115 meeting)
Maybe your system is IPv4 only (for shame), but NAT64 ought work if you used DNS names.
My guess is that you don't use getaddrinfo() properly, or you have an IPv4 literal in the process that gets the QRcode.

Steps to Reproduce

1. visit NAT64 network.
2. attempt to get a QRcode to link laptop to phone
3. watch spinning as QRcode never loads

Actual Result:

fails to get QRcode

Expected Result:

it should work.
Switched to IETF legacy network (with literal IPv4 support), and it worked

Screenshots

Platform Info

Signal Version: 5.63.0

Operating System: ubuntu 20.04LTS

Linked Device Version:

Link to Debug Log

https://www.sandelman.ca/tmp/dyas-signal-debuglog.txt
I guess none of your stuff works over IPv6.

[alexhaydock]

I think this issue is a duplicate of #4121 and should probably be closed, but that is still an active bug and I can confirm that it affects more than just Linux desktops. I can replicate this on Windows 11 too.

[jamiebuilds-signal]

Closing as duplicate