Use the result to make the next technical decision.
ALPN can confirm an HTTPS connection selected h2 or HTTP/1.1. Alt-Svc can show that the server advertises an h3 endpoint to capable clients.
HTTP protocols
See which HTTP protocol signals the HTTPS service exposes.
Inspect ALPN negotiated during modern TLS handshakes and the Alt-Svc advertisement returned by the HTTPS endpoint.
Result
Diagnostic result
Read observations in context.
An h3 Alt-Svc advertisement is not proof that this scanner negotiated QUIC/HTTP/3. Advertised capability and negotiated protocol are reported separately.
Marketing analytics never receive the target.
DotMoose records only the tool name and a coarse success/error outcome for marketing analytics. Active server diagnostics use bounded operational security logs without placing the entered domain, IP, URL, DNS answer or report contents into marketing telemetry.
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