Follow HTTP/2 best practices

[Alanaktion]

HTTP/2 is awesome, and browser support is already pretty good. Our browser support is already quite limited due to the crypto and worker requirements, and most browsers that support our base application-level requirements also at least partially support HTTP/2. Because of this, we shouldn't optimize the site for HTTP 1.1, we should take advantage of HTTP/2's parallel asset loading and connection re-use.

Basically we should keep minifying, but stop concatenating. Defering loading of extra assets via custom JS should be avoided, we can use async instead for most things and HTTP/2 will load them in parallel, so there's no real delay in most cases.

There are plenty of comprehensive articles detailing the differences for development, here are a few:

• https://blog.cloudflare.com/http-2-for-web-developers/
• https://www.smashingmagazine.com/2016/02/getting-ready-for-http2/