There are lot of also very old topics on this.
Latest if find this repy from @Ilia
Whether Virtualmin Pro supports http/2 and Nginx reverse proxy with GUI option
Yes, and Virtualmin GPL as well. However we are only about to release new Nginx/Nginx SSL modules updates with support of http/2
That Nginx/Nginx SSL HTTP2 is now.
Apache only then?
A newer upto date howto / docs about this? With Matrix yes no supported OS and… yes no in Virtmin GUI …