I am asking to add the http3 feature to curl in future debian version releases. Now http3 with openssl and ngtcp2 is no longer experimental. The curl package doesn't have the http3 feature. You can also see details here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=940519
to test if curl has a http3 feature run: curl --version. on ubuntu 25.10 (yes I have ubuntu and not debian, sorry guys): root@3b2013441558:/# curl --version curl 8.14.1 (x86_64-pc-linux-gnu) libcurl/8.14.1 OpenSSL/3.5.0 zlib/1.3.1 brotli/1.1.0 zstd/1.5.7 libidn2/2.3.8 libpsl/0.21.2 libssh2/1.11.1 nghttp2/1.64.0 librtmp/2.3 OpenLDAP/2.6.9 Release-Date: 2025-06-04, security patched: 8.14.1-1ubuntu2 Protocols: dict file ftp ftps gopher gophers http https imap imaps ipfs ipns ldap ldaps mqtt pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp ws wss Features: alt-svc AsynchDNS brotli GSS-API HSTS HTTP2 HTTPS-proxy IDN IPv6 Kerberos Largefile libz NTLM PSL SPNEGO SSL threadsafe TLS-SRP UnixSockets zstd But in the recent version of curl and openssl and ngtcp2 something is changed. They decided to collaborate, and now you can compile curl with openssl and ngtcp2 and nghttp3 to have http3 feature. to compile curl with http3 need: openssl 3.5 and above ngtcp2 version 1.12 and above nghttp3. https://curl.se/docs/http3.html
