Thu Jul 30 18:59:40 2020, original submission:
Reference:
https://tex.stackexchange.com/questions/555636/why-does-make4ht-generate-an-extra-in-this-math-expression
To document this officially, I am posting this here also. screen shot at above link.
=====================
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[
W = \begin{vmatrix}
\sqrt {x} & {x}^{{\frac{3}{2}}} \\
{\frac {1}{2}{\frac {1}{\sqrt {x}}}} & {\frac {3}{2}\sqrt {x}}
\end{vmatrix}
\]
\end{document}
==============
Compiled using
make4ht foo3.tex "mathjax"
tex4ht produces ":" in raw HTML before mathjax process it. Here is raw HTML
===============
<html lang='en-US' xml:lang='en-US'>
<head><title></title>
<meta charset='utf-8' />
<meta content='TeX4ht (https://tug.org/tex4ht/)' name='generator' />
<meta content='width=device-width,initial-scale=1' name='viewport' />
<link rel='stylesheet' href='foo3.css' type='text/css' />
<meta content='foo3.tex' name='src' />
<script> window.MathJax = { tex: { tags: "ams", inlineMath: [ ["\\\(","\\\)"] ], displayMath: [ ['$$','$$'], ["\\[","\\]"] ], processEscapes: true, processEnvironments: true, packages: ['base', 'color', 'ams'] }, loader: { load: ['[tex]/color', '[tex]/ams'] } }; </script>
<script async='async' src='https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-chtml-full.js' id='MathJax-script' type='text/javascript'></script>
</head><body>
<!-- l. 25 --><p class='noindent'>\[ W = \begin{vmatrix} \sqrt{x} &{x}^{{\frac{3}{2}}} \\:{\frac{1}{2}{\frac{1}{\sqrt{x}}}} &{\frac{3}{2}\sqrt{x}} \end{vmatrix} \]
</p>
</body>
</html>
==========================
TL 2020 on Linux
>make4ht --version
make4ht version v0.3e
| 
Related Recipes:
tex4ht - Bugs: bug #479, tex4ht generate an extra : in this...