Issue with header in README.md

[AntoineD]

When a README.md has a header (like a licence header) as a html comment, like so with one of mkdocs gallery's projects examples docs/examples/no_output/README.md:

<!--
  Header here.
-->
## No image output examples

This section gathers examples which don't produce any figures. Some examples
only output to standard output, others demonstrate how Mkdocs-Gallery handles
examples with errors.

The rendering is broken:

[smarie]

Hello @AntoineD , thanks for reporting this issue !

This is strange: mkdocs is supposed to correctly tackle markdown pages containing such a header.

When I try to reproduce the issue, the page concatenating all README.md displays correctly (on the right), including the html comment (if I look at the source). The problem seems "just" that the name of the subgallery is not correctly detected so the toc entry appears blank (left)

Do you confirm ? If so, the fix should improve the subgallery name detection script extract_readme_title (making it robust to the presence of one or several leading HTML elements), but not remove the HTML comment and users who wrote it might want it to eventually be integrated in the final generated html.

[AntoineD]

Hello @smarie,

I'm surprised that you can not reproduce the same rendering. I obtained it by running nox -s docs on my PR without the fix.

Anyway I agree that the comment shall not be removed in the end, I'll change that.

[AntoineD]

@smarie Would it be possible for you to make a release with that fix?

[smarie]

Hi @AntoineD , yes it was done 0.8.0 and 0.9.0 integrate it :)