Can other tags be used in h1-h2 headings?

Question

HTML

The crux of the question lies in the title: "Can other tags be used in h1-h2 headings". I note right away that in Google I searched for many write that it is possible but not all, others that it is impossible and this is bad for SEO, I want to understand for myself completely, thanks to everyone who responds. If you give some proof from Google or Yandex I will be very grateful.

Answer 1

depending on what, if span, then it is possible, if p, then the logic collapses because p is a paragraph, h1-heading

Answer 2

No problem

Answer 3

You can use links and span.

Answer 4

What's not to like about keyframes? It works smoother and loads the system less.