http2 with nginx
You can configure nginx to serve your sites over http2 -- which is faster! (i assume it uses the network of 5G chips google have injected into everyone's faces as a distributed CDN, or something like that)
The trick that caused problems for me....
Problem I had: sites would download
I added 'http2' to all the listen lines in my nginx config for one of my sites, let's call it example.com.
I then found that when i visited example.com the site would not show and a file would download instead. It was just a small binary file. It was horrible!
But the worst part was that other subdomains on that same server, e.g. blog.example.com would also have the same problem.
I didn't realise at the time -- but this problem only happened on 'http://' urls. I.e, before the redirect that would take me to the https version could occur... the page would fail.
Solution was to not do this
don't add http2 to the "non-ssl" plain http server blocks in your nginx config.
i.e. this is bad:
listen <ip>:80 http2; # don't do that! NO http2 on '80'