Which part appears to move, the inset or the surround?pic.twitter.com/vMYXO0NDa0
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For me, the surround appears to move leftward whereas the inset appears to be stationary as long as I see it in the central vision.
For me the inset moves to the right 
Same here. However, I can make it stop moving when I focus on the center in an »unfocused way« (if that makes sense).
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