Include mathjax equations in CHM file

Question

I'm looking to create a chm file with a topic with some mathjax equations. The html file corresponding to the topic is very simple:

<html>
  <head>
    <script type="text/javascript"
            src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
    </script>
  </head>
<body>

<p>
  When \(a \ne 0\), there are two solutions to \(ax^2 + bx + c = 0\) and they are
  $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$
</p>
</body>
</html>

When I compile in HTML Help Workshop, it's all good. But when I open the resulting chm file and navigate to that topic, I get this issue:

and then the equations don't render - I just get whatever is written in plain text mode. Is there any way at all to get mathjax equations render properly in a chm file?

jonjbar · Answer 1 · 2023-01-25T10:33:37.670

The CHM help file format is very old and hasn't been updated by Microsoft in a long time: internally it still uses a very old version of Internet Explorer to display the content of the topics.
Recent versions of MathJax are not compatible with older web browsers and that is probably why you are seeing this error.

To avoid this problem, you can either:

Use an older version of MathJax which is compatible with older web browsers such as Internet Explorer 6
Create a hyperlinks in your CHM help file to a webpage which shows the problematic content: it will be opened by the system's default web browser which is (almost) guaranteed to be much newer
Some help authoring tools also include a way to change the Internet Explorer compatibility settings which could be used to force Microsoft Edge to be used to display content: it should allow MathJax to run properly

score 0 · Answer 2 · answered Jan 25 '23 at 11:49

MathJax used to be able to work in CHM files, but it was a bit fiddly to get it to work. As I recall, you had to use an explicit configuration rather than the ?config=... approach for one thing. There are some very old discussion about it in the MathJax user's forum; see here. it was always a bit difficult to get it to work, and these discussions were about very early versions of MathJax (v1.1, v2.0, v2.1), so you might need to explicitly select older versions of MathJax. Also note that the cdn.mathjax.org address was retired in 2017 (it still exists, but redirects to another CDN, and that might also be a problem for CHM files), so you may want to use one of the other CDNs that serve MathJax, e.g., cdn.jsdelivr.net/npm/mathjax@2/MathJax.js, instead.

help-info.de · Answer 3 · 2023-01-26T11:18:21.893

As a first simple step you'd try to add following line into your HTML topic files:

<meta http-equiv="X-UA-Compatible" content="IE=11">

Tested and compiled by using FAR HTML with HTML file shown below and some css stuff. I did a reverse test by deleting the line mentioned above only and the script error window appears again.

For further information using X-UA-Compatible see also: https://stackoverflow.com/a/6771584/1981088

<html>
  <head>
  <meta http-equiv="X-UA-Compatible" content="IE=11">
  <title>MathJax Test</title>
    <script type="text/javascript"
            src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
    </script>
  <link rel="stylesheet" href="../design.css">
  </head>
<body>
<h1>MathJax Test</h1>
<p>
  When \(a \ne 0\), there are two solutions to \(ax^2 + bx + c = 0\) and they are
  $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$
</p>
</body>
</html>

is resulting in a CHM topic like this:

Of course you need a internet connection.

Include mathjax equations in CHM file

3 Answers3