Empathy test for color blindness and visual impairment. This add-on emulates 8 types of color blindness, plus grayscale to check the contrast of your website.
https://vinceumo.github.io/A11Y-Color-Blindness-Empathy-Test/
Issues: https://github.com/vinceumo/A11Y-Color-Blindness-Empathy-Test-browser-extensions