@Louis Thanks for explaining the flip-flop.
Maybe we can convince @Jason to make a new version of his ESP32 shield that includes a flip-flop. Until then, it would be too much weird soldering on top of his board, so I think I’ll continue without it.
Looking forward to an ESP32 smartmatrix shield, though
Yes, what saved me is that the room is dark and I’m very bright, so the camera switches to a longer shutter speed, giving the time to the display to update enough that scanning is not visible.
I still need to check @seratosteve 's fork when I get a chance, unless you get to it first. It’d be great if it were a regular github fork though, easier to diff