> in Apache HTTP Server’s HTTP/2 module (mod_http2)
I feel like in hindsight, HTTP/2 was a mistake. The theoretical benefits just don't justify the added complexity. It definitely shouldn't have been fasttracked like it was.
I don't think it was fast tracked. Was it? I heard the rational to do HTTP 2 and soon later HTTP 3 was to split improvements and ease transition.
But if you have more then one httpd server - eg. some fcgi - then HTTP/1.1 is almost architectural backdor: HTTP Request Smuggling, at minimum.
Apache even don't have it's own HTTP/2: mod_http2 use external library nghttp2[.org] so Apache is dead shell at this point.