ccing folks who might know of work that was done:

+peconn as I recall he was doing video related things in the past.
+tedchoc since this is a fullscreen manager issue.

This is causing an issue where tapping on the bottom sheet at the same time a video is fullscreened results in the sheet being opened on top of the video. Not a very severe bug, but a bug none the less.

+mlamouri

Are you saying that onToggleOverlayVideoMode isn't called at all or just not in the bottom sheet?  I don't know what triggers that signal and whether the changes to the video stack make it still relevant.

I wonder if there is a different signal we should use when you enter fullscreen.  I'm not sure there is an observable method when the fullscreen web api is triggered to be honest.  Maybe hasEffectivelyFullscreenVideoChange on WebContentsObserver?

hasEffectivelyFullscreenVideoChange (and hasActiveEffectivelyFullscreenVideo) rely on a heuristic so aren't triggered immediately when a video goes to fullscreen. They may not be the best place to put that logic. mlamouri@ may have more information.

I can't seem to get onToggleOverlayVideoMode called at all. I'd expect this to be triggered for sites like youtube and bbc when viewing fullscreen videos, I may be mistaken though.