Jean-Frederic and All, As a packager of https://codeit.guru/ I am also very interested in improvements on mod_http3.
Some of my code is already in trunk (QPACK, mod_ssl TLS environment, rejecting malformed requests and others). I started single PR https://github.com/apache/httpd/pull/947 with small ones: one fixes a crash, graceful restart that never finishes and blocked-stream spin. Also we tested much more that include mod_ssl apr certificate inheritance and running it well. Can I proceed with heavier ones - which we also happy with? Thank you for your time!
