It was just a little, stupid experiment that has got me into this (again). As someone who has worked on websites and image conversion software I thought I saw most of the strange behaviour of software, monitors (or printers!) color-profiles and the effects ofcombinations of mismanagement of any of these. How I was wrong.
The experiment had everything to do with colour and nothing to do with color representation on a screen or sheet of paper. I tried to create a loop through some rgb values by increment or decrement of 1, going rgb(255,0,0) -> rgb(255,255,0) -> rgb(0,255,0) -> rgb(0,255,255) -> rgb(0,0,255) -> rgb(255,0,255) and back to the beginning. I've got that working but I'm stuck with this where both reds think they are 255,0,0 but one of them obviously is not.
![firfox displaying an image on a red background] (https://xiffy.nl/images/red/firefox-red-image-red-background.png) while the ![new edge browser displays the webpage like so] (https://xiffy.nl/images/red/edge_red_on_red.png)
So what do we see? Well it's an html-page, with background-color set to #FF0000, or rgb(255,0,0). On that page there is a png image. This image is made on my machine, which is used for the screenshot with Gimp. I created an empty image and set the color to #FF0000 and exported the image as a png.