What would you like to be added:
Currently, the CoreDNS supports various protocols clients can use to connect to the CoreDNS instance. Among those protocols is a DoH (with HTTP/2).
It might be worth considering adding the support for HTTP/3 as well as it gains popularity.

Why is this needed:
We are using CoreDNS as a DNS resolver for Mobile devices all around the world. With the current trends, it seems that
new versions of operating systems on mobile phones are gradually adding support for DoH3.

Examples

• https://security.googleblog.com/2022/07/dns-over-http3-in-android.html
• It seems that it might be part of the iOS 17

Is this something you'd consider adding to the CoreDNS?