Overview

Comments are not interpreted when parsing markdown strings.

Expected behavior

Markdown comments are parsed, similar to many other lexers. For example, in Python:

from pygments import highlight
from pygments.lexers import PythonLexer
from pygments.formatters import HtmlFormatter
code = "print('hello world')  # (1)"
print(highlight(code, PythonLexer(), HtmlFormatter()))

Produces the following string:

<div class="highlight"><pre><span></span><span class="nb">print</span><span class="p">(</span><span class="s1">&#39;hello world&#39;</span><span class="p">)</span>  <span class="c1"># (1)</span>
</pre></div>

Actual behavior

Markdown comments are not parsed. The following parsing:

from pygments import highlight
from pygments.lexers import MarkdownLexer
from pygments.formatters import HtmlFormatter
markdown = "# Something <!--- (1) --->"
print(highlight(markdown, MarkdownLexer(), HtmlFormatter()))

Produces the following string:

<div class="highlight"><pre><span></span><span class="gh"># Something &lt;!--- (1) ---&gt;</span>
</pre></div>

Practical implication

Who cares? Well, pygments is popularly used within packages such as mkdocs-material to parse fenced code.
The current funcitonality limits the ability to use features of certain packages built on top of pygments, such as code annotations in mkdocs-material.

Environment

System: MacOS
pygments version: 2.13.0

Thank you in advance for taking the time to look at this, and I greatly appreciate the pygments package, as well as its development team.