Fix compatability with Procban #6
Description
Procban is a procedurally-generated Sokoban game by Egor Dorichev.
picolove CANNOT run this game. For a build that demonstrates just how much picolove fails, see here (WARNING: Flashing lights may cause seizures).
Seemingly, this is a graphical issue first and foremost. Fixing the graphical issue just might make it playable.