h7-h9 via aria-level elements h7 - h9
elements h1
element, with role="heading" & aria-level="7"
h2
element, with aria-level="8" h1 - h6 + aria-level 7 - 12
elements with no content h7 - h12 (aria-level 7 - 12)
elements with aria-label role=heading + (aria-level 7 - 12) on div
elements