Honestly I print out anything my little kiddo does at school on his Chromebook, and some stuff has black backgrounds. I got tired of wasting toner so I made a script that would print a negative screenshot if it’s a dark image. One keystroke and I get what I want
This is probably going to be an unpopular opinion, but here it is anyway. If it doesn’t come off with dish detergent and a scrub sponge, just call it a permanent seasoning and let it be. If scrubbing it like mad won’t make it come off, then it won’t come off if your food touches it.