MathJax version 3 support

On the Math & Equations page, there is a note that MathJax 3 can be used by configuring the mathjax_path. However, if you have any other MathJax configuration (e.g., custom macros) these will not be converted to the new configuration format for MathJax 3. It seems that Sphinx does not yet support the new configuration format either; the pull request that switched Sphinx over to MathJax version 3 didn’t address the configuration changes. See also: http://docs.mathjax.org/en/latest/web/configuration.html#converting-your-v2-configuration-to-v3

I think one way to resolve this issue would be to modify the note in the Jupyter Books docs to say something about other configuration options not being suported at the moment.

[mmcky]

@choldgraf did some testing today and we are finding there are still incorrect renderings of math using chtml on safari as per comments in https://github.com/QuantEcon/lecture-python.myst/pull/179.

[mgeier]

@chrisjsewell

Really, the ideal behaviour for MathJax, would be to only render text in specific HTML elements […] rather than arbitrarily searching in the text for delimiters like \\[...\\].

I don’t know whether that’s possible, but it’s possible to limit the search for delimiters to certain HTML elements.

In the pre-MathJax-3 era this was done with ignoreClass and processClass (which, for example, I’ve used there: https://github.com/spatialaudio/nbsphinx/blob/d5d352c5440cc7a185751bdf0d1ba263b7a2026d/src/nbsphinx.py#L2237-L2245).

With MathJax 3, this should become something like the following (but I haven’t tested this yet!):

window.MathJax = {
  options: {
    ignoreHtmlClass: "document",
    processHtmlClass: "math|output_area"
  }
};