Since HTTP/3 support has landed in stable versions of nginx, I think it's time to update the sample configurations for nginx to enable HTTP/3 support.

After applying the guide at nginx.org, I encountered the access through untrusted domain-page preventing me from using it as-is, so there seems to be more to it than just that.

Here are the additions for the server-block I used:

listen 443 quic reuseport;
listen [::]:443 quic reuseport;
add_header Alt-Svc 'h3=":443"; ma=86400';
quic_retry on;
quic_gso on;
ssl_early_data on;
proxy_set_header Early-Data $ssl_early_data;