Comment by Bartweiss

> other metadata (eg printer-specific output artifacts)

This is actually a really good point. I've been rolling my eyes a bit at people smugly pretending they knew what DocuColor was last week, or equating it with things like EXIF data that are far more widely known.

But you don't have to know about DocuColor specifically to avoid this issue, you just have to suspect that printer outputs are a threat vector for something identifiable.