I was wondering if there would be any problems if I added a list inside a H1 heading:
Header elements like follow the phrasing content content model: if you wanted to follow the HTML specification to the letter, phrasing content can only contain regular text or other phrasing content. As
elements aren't phrasing content, they're technically not allowed in elements.
Your second example—placing the elements within
elements—is valid markup and would be the preferred method of combining
and
elements.