MathJax v2 Configuration

In _includes/head_custom.html add, for example:

{% case page.math %}
     
  {% when "mathjax2" %}

    <script type="text/x-mathjax-config">
      MathJax.Hub.Config({
        TeX: { 
          equationNumbers: { autoNumber: "AMS" }
        }
      });
    </script>
    <script type="text/javascript" async 
      src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.7/latest.js?config=TeX-AMS_SVG">
    </script>
   
{% endcase %}

In the front matter of pages using MathJax v2 (or as a global front-matter default) add:

math: mathjax2

The suggested field name math and the key mathjax2 can be replaced.