What are the options here? Can I have them be only visible when printing? Does it mirror itself if I print double-sided? Maybe pdf does not support these things, but to me these are the important questions.
It’s visible in the PDF. I have used that extension to mark draft versions of documents. This makes it very obvious and saves you from accidentally handing in a draft. At least back when things were printed out much more often. With PDFs I find that the file name is sufficient.
you chose where to place it:
https://ctan.mirror.garr.it/mirrors/ctan/graphics/pgf/contrib/coffeestains/coffeestains-en.pdf
Does PDF actually allow some objects to be invisible on screen but visible on print? Because that’d be cool.
It’s 2225. Archaeologists discover yet another long forgotten university library storage facility. Inside, they find stacks of Elsevier journals that have never been opened. They then find puzzling coffee stains that somehow appear to be result of the printing process, and conclude that the cultural significance of these markings was probably lost to the ages.
