Fullscreen reordering behavior

[josepharhar]

MDN URL

https://developer.mozilla.org/en-US/docs/Web/API/Fullscreen_API

What specific section or headline is this issue about?

No response

What information was incorrect, unhelpful, or incomplete?

In this HTML PR, the behavior of requesting fullscreen on multiple elements was defined. This test shows how it should work: if you call requestFullscreen on an element A, and then call requestFullscreen on an element B, they should both be in the top layer, and B should be on top. If you then call requestFullscreen on element A again, then A should now be on top.

What did you expect to see?

There could be a section explaining this top layer stacking/reordering behavior

Do you have any supporting links, references, or citations?

whatwg/html#9093
web-platform-tests/wpt#39828

Do you have anything more you want to share?

No response

[foolip]

FWIW, I think a like requesting in A-B-A order is a bit too esoteric to document, but it would be useful to document that nested fullscreen is a thing, and that it's possible to request fullscreen of different elements in any order. Possibly there should be a note that some browsers require the 2nd fullscreen element to be a descendant of the 1st, so that it's not possible to request fullscreen of a sibling (or ancestor) element of the current fullscreen element.

[Josh-Cena]

Seems like both Chrome and Firefox already implement the new behavior, but Safari does not; maybe when Safari fixes this, we would also need a BCD note.