We've just upgraded our HTML validation servers to the latest version of the W3C validator, 20.3, which was released today and includes many changes in the validation rules, so you may want to re-check your sites to get the most up-to-date results.
This release provides a number of improvements in ARIA role checking and in CSS checking, as well as support for checking a number of HTML features that weren’t supported previously: * Disallow `accept-charset` values other than UTF-8 * Disallow `object[typemustmatch]` * Allow SVG `feDropShadow` element (from Filter Effects spec) * Allow `loading` attribute for the `img` element (lazy loading) * Allow `rel=modulepreload` for the link element * Allow `integrity` attribute on `link[rel=preload|modulepreload]` * Allow `integrity` attribute on `script[type=module]` * Allow `autofocus` as a global attribute * Allow `inputmode` as a global attribute * Allow `nonce` as a global attribute * Allow `allow-downloads` in `iframe[sandbox]` * Allow `heading` content within `legend` element * Allow negated media features in `media` and `sizes` attributes * Align `autocomplete` checking with current spec * CSS: Improve support for color values * ARIA: Allow implicit roles to satisfy owned-by requirements * ARIA: Add proper ARIA checking for the `math` element * ARIA: Align all role checking with current HTML-ARIA spec ## Time to re-check your sites!As usual, it's recommended to re-check your sites after the validation servers have been upgraded, to get the most up-to-date results. Remember that you can schedule your reports to run periodically, so you don't have to do that manually every time.