test mathjax preamble instead of pngmath

[LM]

[LM]

It is working now.

It seems that the fluid language for theming use # as comment which means # in preambles should be escaped.

Escape #

<script type="text/x-mathjax-config">
    MathJax.Hub.Config({ TeX: { extensions: ["color.js"] }});
  </script>
  <script type="text/x-mathjax-config">
    MathJax.Hub.Config({
      tex2jax: {
        skipTags: ['script', 'noscript', 'style', 'textarea', 'pre', 'code']
      }
    });
</script>
<script type="text/x-mathjax-config">
    MathJax.Hub.Queue(function() {
        var all = MathJax.Hub.getAllJax(), i;
        for(i=0; i < all.length; i += 1) {
            all[i].SourceElement().parentNode.className += ' has-jax';
        }
    });
</script>
<script type="text/x-mathjax-config">
  MathJax.Hub.Config({
    tex2jax: {
      processEscapes: true
    }
  });
</script>
  <script type="text/x-mathjax-config">
  MathJax.Hub.Config({
    TeX: {
      Macros: {
        overlr: ['\\overset\\leftrightarrow{\#1}',1],
        overl: ['\\overset\leftarrow{\#1}',1],
        overr: ['\\overset\rightarrow{\#1}',1],
        bra: ['\\left\\langle \#1\\right|',1],
        ket: ['\\left| \#1\\right\\rangle',1],
        braket: ['\\langle \#1 \\mid \#2 \\rangle',2],
        avg: ['\\left< #1 \\right>',1],
        bold: ['\\boldsymbol{\#1}',1]
      }
    }
  });
  </script>
  <script type="text/javascript" src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
  </script>