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WAVE (browser plugin), https://wave.webaim.org/
Lighthouse (built into Chrome dev tools)
axe DevTools (browser plugin)
“Color Blindness Simulator,” https://www.craigabbott.color-blindness.com/coblis-color-blindness-simulator/co.uk/blog/axe-core-vs-pa11y/
a Firefox web developer addon, https://addons.mozilla.org/en-US/firefox/addon/web-developer/
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