Old video, only 480p, that I dug up to play around with Cyberlink Power Director 12.
Chips from the square cutter tend to fly straight back at your fingers and if the wood is just the right hardness, will give you a thousand little paper cuts and that isn’t fun. Commercial versions seemed expensive for a piece of plexiglass so here is a simple shop made version. Changes I would make are bigger magnets and a shorter wood base. I keep meaning to cut these down.