My current favourite example is the MDN page covering text contrast — https://developer.mozilla.org/en-US/docs/Web/Accessibility/Understanding_WCAG/Perceivable

My current favourite example is the MDN page covering text contrast — https://developer.mozilla.org/en-US/docs/Web/Accessibility/Understanding_WCAG/Perceivable https://developer.mozilla.org/en-US/docs/Web/Accessibility/U... — which violates the rules it states. (As does practically all of MDN, but particularly the confetti-factory code samples.)