[fullscreen] Dialog while in fullscreen causes fullscreenElement to return null? (#13)

https://fullscreen.spec.whatwg.org/#dom-document-fullscreenelement

> The fullscreenElement attribute's getter must return the top element of the context object's top layer if that element has its fullscreen flag set, and null otherwise.

Similar to https://github.com/whatwg/fullscreen/issues/10 and https://github.com/whatwg/fullscreen/issues/12

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fullscreen/issues/13