[tex4ht] underline math does not work in tex4ht when in mathjax mode

Sat Apr 6 08:36:53 CEST 2019

Hello experts:

Is this a known issue? \underline does not show at
all under math when using mathjax

When using SVG it does it show up correct (also in pdf it
shows OK).

MWE
----------------------------------
\documentclass{article}
\usepackage{amsmath}
\begin{document}

$\left(  AB\right)  ^{T}=B^{T}A^{T}$

%underline does not show under the math part
\underline{Some text $\left(  AB\right)  ^{T}=B^{T}A^{T}$}

%underline shows up ok for text only
\underline{Some text}
\end{document}
--------------------------------

When compiled using

make4ht foo.tex "mathjax"

No underline shows at all under math.

Googling around, it seems underline show work in mathjax
but not sure.

The HTML generated looks like this for

\underline{Some text $\left(  AB\right)  ^{T}=B^{T}A^{T}$}

<p class="indent">
<span class="underline">Some text \(\left ( AB\right ) ^{T}=B^{T}A^{T}\)
</span>

But the underline does not extend to the math part.

Is this a mathjax issue itself or make4ht is not doing
something right?

Using TL 2018

The full HTML is
===============================
<html lang="en-US" xml:lang="en-US" >
<head><title></title>
<meta  charset="iso-8859-1" />
<meta name="generator" content="TeX4ht (http://www.tug.org/tex4ht/)" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<link rel="stylesheet" type="text/css" href="foo.css" />
<meta name="src" content="foo.tex" />
  <script type="text/x-mathjax-config">
MathJax.Hub.Config({ 'fast-preview': {disabled: true},
TeX: { extensions: ["color.js","AMSmath.js"], equationNumbers: { autoNumber: "AMS" } },
extensions: ["tex2jax.js"], tex2jax: {  inlineMath: [ ["\\\(","\\\)"] ],
displayMath: [ ['$$','$$'], ["\\[","\\]"] ],
processEscapes: true, processEnvironments: true } }); </script>
  <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/latest.js?config=TeX-AMS-MML_HTMLorMML"></script>
</head><body
>
<!--l. 7--><p class="noindent" >\(\left ( AB\right ) ^{T}=B^{T}A^{T}\)
</p><!--l. 9--><p class="indent" >   <span class="underline">Some text \(\left ( AB\right ) ^{T}=B^{T}A^{T}\)</span>
</p><!--l. 11--><p class="indent" >   <span class="underline">Some text</span> </p>
</body>
</html>
====================================

Thanks
--Nasser