How to highlight Markdown inside HTML without a blank line?

[LeaVerou]

I noticed that marked does not support anything like the markdown="1" attribute of other Markdown parsers. (see #488) and that after #1135, a blank line is required to switch to Markdown mode again.
While this works for things like <div>, it does not work for highlighting Markdown inside e.g. <p>.

It seems I can use the html() token in Renderer or Tokenizer to fix this, but I'm not sufficiently familiar with Marked's internals. Has anyone else figured this out?

[UziTech]

#1907 (comment)