I can only server contents with IPv6 because I'm sitting behind CGN on IPv4. When enabling HTTP2 it still not serve contents with HTTP2 as there are missing arguments in the `listen`. But it still does the SSL encryption.
Previous to this commit it generates:
```
listen 80;
listen [::]:80;
listen 443 ssl http2;
listen [::]:443;
```
Now it generates:
```
listen 80;
listen [::]:80;
listen 443 ssl http2;
listen [::]:443 ssl http2;
```
f022e84979