Runwar has supported HTTP2 for a while, but it seems it's off by default and we don't have a first class setting to turn it on.
Right now, If you want to enable it you can run the following command:
which puts the following in your server.json
Find a good place in the server.json for a dedicated setting. I'm not sure we can force it to be enabled by default since it seems to require SSL to also be enabled.