> Far from it. It's quite likely going to be over 5 years if not a decade before it would be possible to run a pure-HTTP3 service without risking connectivity p

> Far from it. It's quite likely going to be over 5 years if not a decade before it would be possible to run a pure-HTTP3 service without risking connectivity problems There won't be a pure HTTP/3 service anyway. HTTP/3 requires negotiation. It is announced from a previous HTTP/1.1 or /2 request using a "Alt-Svc" header. Typical clients will not try to connect using HTTP/3 directly