moderated Re: section links #suggestion
I too noticed this when looking at https://help.github.com/en/github content.
That is one reason I promote the idea of using a Table of Contents (ToC) for longer pages.
The page you reference uses similar functionality, it even has it's own "ToC" at the top although it is in a different format. Not sure how it differs in the underlying code but if you are looking for the functionality, the ToC works like a charm.