Museum Fold, a 8x8 Patches puzzle
Arrow keys move. Enter starts a rectangle; arrows resize it; Enter places it. Escape cancels. Delete removes a patch. Control or Command Z undoes.
About this board
Five 8s, and every one becomes a 4x2 block, but only after you rule out the alternatives. The tall 6 in the bottom row is the single fixed patch. From there it is a careful stacking job, because several 8s could fit more than one way until a wrong choice would leave a neighbour with no room. The left half ends up as four identical drawers stacked on top of each other.