Is it semantic to insert an svg tag into a button?

Question

HTML

Actually, caniinclude shyly averted his eyes) who knows?

Answer 1

We climb into the spec, look at the Content model of the button parent tag - we see "Phrasing content, but there must be no interactive content descendant and no descendant with the tabindex attribute specified".
We look at the tags in Phrasing content and see our svg there.