- General accessibility guidance
- The A11y Project: https://www.a11yproject.com/
- Slides on A11y in Wordpress (most of the slides are universally relevant -- unless they mention WP specifically): https://www.slideshare.net/mtoppa/a11y-i18n-l10n-utf8-wtf-understanding-the-connections-between-accessibility-internationalization-localization-and-character-sets-long-version
- A11y in Mapping and Visualization
- Color Brewer 2.0: https://colorbrewer2.org/
- Issue around a11y best-practices in Leaflet: Leaflet/Leaflet#8006
- Issue for improving a11y for vector data in Leaflet: Leaflet/Leaflet#8251
- Web Content Accessibility Guidelines (WCAG)
- Moizlla Developer Network - Understanding the Web Content Accessibility Guidelines: https://developer.mozilla.org/en-US/docs/Web/Accessibility/Understanding_WCAG
- List of Axe rules (you will find a link to these when Axe finds a WCAG violation in your HTML): https://dequeuniversity.com/rules/axe/4.5/