‘Markdown’ isn’t well defined, but here are a few that I think apply:
- headers and footers on pages
- starting chapters on a new page
- having pages, to start with
- tables where cells have multiple lines of content
- pages with multiple columns of text
- drop caps
- ‘watermarks’ on pages (e.g. a diagonal “Concept” below the text)
- centering or full justifying paragraphs
- multiple kinds of underlines.
- text colors
- control over character and line spacing
- embedded JavaScript (https://helpx.adobe.com/acrobat/using/applying-actions-scrip...)
- DRM :-) / :-(
> Not to mention embedded HTML could cover even more where Markdown is lacking
Yes, you could use that to include JavaScript for a PDF or ePub renderer and then render those on-page :-)
But most classic literature can be just txt file (and it is)