I would take an alternative position in this matter. What we need is a simple yet functional subset of web. The point is to be able to build a browser in a reasonable amount of time with many languages reusing some commonly used libraries, while being able to use latest Chrome to browse those websites as well.
TLS: keep it as it is. Crypto is hard and TLS is proven crypto. Mandate something like 1.2+ and be done with it. Every mature language has TLS implementation or bindings.
HTTP: use subset of HTTP/1.1. Parsing is very easy: it's just bunch of lines. Full HTTP/1.1 is hard and probably unnecessary. Things like connection reuse are not necessary and should be excluded for simplicity.
HTML: use subset of XHTML. It must be valid XML, so parsing is just one call to the XML library which is available on every language.
CSS: I don't really know, that's a tough one. Something like CSS 2 I guess. There must be a balance between complexity of implementation and richness of presentation.
JavaScript: just nope. That rabbit hole is too deep.
If you take this position to the extreme, you can even reduce HTML + CSS to some kind of markdown-like language, but I don't think that we need to go that far.
TLS: keep it as it is. Crypto is hard and TLS is proven crypto. Mandate something like 1.2+ and be done with it. Every mature language has TLS implementation or bindings.
HTTP: use subset of HTTP/1.1. Parsing is very easy: it's just bunch of lines. Full HTTP/1.1 is hard and probably unnecessary. Things like connection reuse are not necessary and should be excluded for simplicity.
HTML: use subset of XHTML. It must be valid XML, so parsing is just one call to the XML library which is available on every language.
CSS: I don't really know, that's a tough one. Something like CSS 2 I guess. There must be a balance between complexity of implementation and richness of presentation.
JavaScript: just nope. That rabbit hole is too deep.
If you take this position to the extreme, you can even reduce HTML + CSS to some kind of markdown-like language, but I don't think that we need to go that far.