Maybe they don't work to rule it out, but I am colourblind (as diagnosed in-person with specially-printed images by a professional optician) and when people have pointed me at these images on computers (only slightly less annoying than 'can you see this?', 'what colour is my shirt?') they've always 'worked' as expected.
This particular website doesn’t work on a computer. I’ve seen others that work well enough. This website is just broken. I believe this version is intended to only be legible if you’re colorblind, but good luck actually using it.
