Datacenter looks good. @sanscontext where's that page with all possible markdown permutations you've created? Is that page OK?

@joaofnfernandes https://deploy-preview-1021--psychologist-duck-16578.netlify.com/test/#/some-code-block-samples
You can compare it with https://docs.docker.com/test/#/some-code-block-samples

Looks pretty good, but looks like YAML changed how it's broken, and it might not have dockerfile?

It seems that Rouge has support for Docker files in their latest version (2.0.7), but
we're importing Rouge through github-pages, which in turn imports Rouge 1.11.1.
https://github.com/jneen/rouge/blob/master/lib/rouge/lexers/docker.rb

While I'd love to do this, Jekyll does not support the Rouge version where Dockerfile support was added (which was 2.0.4). As you see here, it's dependency is set to ~>1.7: https://rubygems.org/gems/jekyll

$ bundle update
Fetching gem metadata from https://rubygems.org/...........
Fetching version metadata from https://rubygems.org/..
Fetching dependency metadata from https://rubygems.org/.
Resolving dependencies...
Bundler could not find compatible versions for gem "rouge":
  In Gemfile:
    rouge (~> 2.0)

    jekyll (~> 3.3) was resolved to 3.3.0, which depends on
      rouge (~> 1.7)

It's not a GitHub Pages thing; no idea when Jekyll will get their act together.

Trying this Gemfile:

source "https://rubygems.org"

gem "rouge","2.0.7"
gem "jekyll-seo-tag"
gem "kramdown"
gem "jekyll-redirect-from"
gem "jekyll","3.3.1"

You get the incompatibility error when running bundle update

Trying this:

source "https://rubygems.org"

gem "rouge","2.0.7"
gem "jekyll-seo-tag"
gem "kramdown"
gem "jekyll-redirect-from"
gem "jekyll"

Succeeds but bundler reverts way back to Jekyll 2.5.3, probably because that was before it had dependency checking for Rouge: https://rubygems.org/gems/jekyll/versions/2.5.3

The very next version past 2.5.3, which was 3.0.0, was when Jekyll pinned its Rouge dependency at ~>1.7 and it has stayed there ever since:
https://rubygems.org/gems/jekyll/versions/3.0.0

In the mean time we can all watch this issue: jekyll/jekyll#5556

Closing in favor of #2757. We can use conf instead of native Dockerfile support for now.