Comment 2 for bug 1930309

This is probably caused by the following dependency chain: mcclim -> opticl -> pngload -> 3bz -> nibbles. I hopefully fixed the nibbles problem in this commit: https://github.com/sharplispers/nibbles/commit/dad25240928d5cf8f7df69c4398244e03570bb35. So things should work again when the nibbles fix gets into Quicklisp.