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Sites behind authentication
WAVE (browser plugin), https://wave.webaim.org/
Lighthouse - (built into Chrome dev tools)
axe DevTools (browser plugin)
a Firefox web developer addon, https://addons.mozilla.org/en-US/firefox/addon/web-developer/
Tutorial
I am not sure how useful LinkedIn learning is for this.
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These tutorials have html examples.
https://www.sitepoint.com/how-to-use-aria-effectively-with-html5/
https://www.a11yproject.com/posts/2014-05-15-getting-started-aria/
https://www.a11yproject.com/posts/2020-08-20-an-indepth-guide-to-aria-roles/ .
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https://picocss.com/WAVE Accessibility online site also offers a browser Extension, https://wave.webaim.org/
"Check Web Site’s (X)HTML & CSS, Accessibility & SEO," https://www.webnauts.net/check.html
“Color Blindness Simulator,” https://www.color-blindnesssmashingmagazine.com/coblis-color-blindness-simulator/a Firefox web developer addon, https://addons.mozilla.org/en-US/firefox/addon/web-developer2024/02/accessibility-standards-empower-better-chart-visual-design/