My own image conversion unit tests usually reveal subtle changes in Apple’s own frameworks. After setting up an M1 Mini as a build server, I discovered a funny behavior that seem to only affect Apple’s M1 frameworks: they can’t preserve Apple Wide Colorspace in image conversions.

I confirmed it’s “not just me” by resizing an image with Apple Wide colorspace in Preview. If I run it in Rosetta, it works. If i don’t, it gets converted to Generic RGB.