How to track video dimension changes (videoRect) while in PictureInPicture (PiP)

I'm trying to get the width and height of an HLS AVPlayer in PiP mode. It seems that you would get this in the videoRect attribute of AVPlayerLayer, but it doesn't seem to update correctly in PiP or background modes (playing a video's audio while in lock screen for example doesn't update width and height to 0 as expected). Any ideas on how to get the video resolution/dimension while in PictureInPicture?

How to track video dimension changes (videoRect) while in PictureInPicture (PiP)
 
 
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