Starting today, every CacheNova zone negotiates HTTP/3 over QUIC when the client supports it, and falls back to HTTP/2 otherwise. There’s nothing to turn on.
QUIC runs over UDP and removes head-of-line blocking that can stall HTTP/2 on lossy networks — exactly the conditions mobile users hit. Connection setup is faster too, which helps first-request latency for users far from your origin.
We advertise Alt-Svc automatically. Clients that don’t support HTTP/3 continue over HTTP/2 with no change in behavior. TLS 1.3 remains mandatory on all protocols.
You can confirm the negotiated protocol per request in your logs and in the /v1/analytics API under the protocol dimension.