In Jan 7, 2022 Stephen Hawking's 80th Birthday Doodle, YouTube show something incredible at 1:22 (01 min and 22 sec) of the video:

Hint is ReactJS Logo which is created by Facebook.

This is just my take on this Doodle video, maybe Google and Facebook aren't going to work together or this logo might be of something else not of ReactJS, what do you think, let me know about your thoughts in the comment section.