If I connect my windows to a vpn server via ipv4, windows thinks that there is no ipv6 connection
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(I guess) TeamSpeak somehow checks the ipv6 connectivity by looking at what windows says -> TeamSpeak thinks there is no working ipv6 connection. Because of that, teamspeak refuses to look up AAAA-Records of domains
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I need to manually enter the ipv6 address to connect to a server that actually has a working domain
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Please implement other checks to see if IPv6 works instead of looking at what windows says. Windows is buggy regarding this and should not be considered as reliable source of information.

My proposal:
Prefer IPv6, no matter what windows says and if it doesnt work, use ipv4 OR TRY ipv6 if the domain has no A-Record although windows says ipv6 is not operational.