Get HTTP/3 to work on nginx

So, Nginx officially supports HTTP/3 since v1.25.0. Instructions on how to set it up are here . As many other people, I tried to set it up myself. But after following every bit of the documentation I couldn't get it to work. I spent a lot of time to try and get it working, to no avail.

I was testing my server to check if it did support TLSv1.3 and this tool left me with an error saying something like:

"your.domain.name <your-ipv6-address> is unreachable"

So, the reason HTTP/3 wasn't working was because the HTTP requests were being tried through IPv6. To double-check, disabling the AAAA record in the DNS, was enough to finally get HTTP/3 to work flawlessly.