The "unsupported protocol" failure was never about HTTPS: the Vita resolved the public domain to the WAN IP, the router (no NAT loopback) answered with its own admin page, and curl reported the resulting HTTP/0.9 garbage as CURLE_UNSUPPORTED_PROTOCOL. serverip= pins the hostname to the LAN IP via CURLOPT_RESOLVE, keeping Host/SNI intact for the reverse proxy. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>