In the GWR2020 in the speedcubing section there is a piece about Stanley Chapel's 4BLD WR single but it shows a picture of him holding a 5x5.
We need some WCA delegates in there. But then to be honest identifying a difference between a 4x4 and a 5x5 in a small pic is harder than it sounds like, I suppose.
First, that is not Sebastian Weyer and the cube in the pic is not even a 4x4.