When editing a post on a site where MathJax is enabled there in "how to format" there is a link Mathjax help which points to a page not as useful as the Mathjax tutorial on http://meta.math.stackexchange.com. So I suggest to replace that link with MathJax basic tutorial and quick reference

Ok, here's how this works: https://legacy-www.math.harvard.edu/texman/ is the default guide for all sites that have MathJax enabled. It's pretty generic, and that's a good thing. Any site with MathJax enabled can request that a different guide be used for this purpose. Ideally, they'll write one...