pngcrush... you had one job 
(I understand that the algorithm may find there's nothing left to crush, but in that case, surely it should return the original file and not a worse one?!)
@0xabad1dea what happens if you try to re-crush a pre-crushed png file? Does it keep increasing, or just remain at the same slightly enlarged size?
@0xabad1dea see also forcing mp4 and webp conversion when whatever was originally uploaded is objectively smaller.
@0xabad1dea the command line version says it will, but I'm not sure if it actually does