The HTML Sanitization that the About HTML Plugin performs removes the markup required to provide Internal Fedwiki Links.
If you try to use markup like this in your HTML:
<a class="internal" href="/about-graph-plugin.html" data-page-name="about-graph-plugin" title="view">About Graph Plugin</a>
It get's sanitized to this:
<a class="internal" title="view">Archive</a>
And in the HTML Plugin functions like this:
Instead of Archive.
This is of course not usually a problem, because you can simply include `your link` tags in your HTML. However if you want to author more complicated HTML such as image maps of embedded svg with links, this does not work.