# Accessibility Checker upgraded to Axe Core 4.13 > Canonical HTML version: https://rocketvalidator.com/blog/accessibility-checker-upgraded-to-axe-core-4.13 > Attribution: Rocket Validator (https://rocketvalidator.com) > License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) Rocket Validator's accessibility validation servers now run Axe Core 4.13. No rules were added or removed, but many existing rules changed, including new support for web components using Element Internals. Your issue counts may change as a result.

We've upgraded our accessibility validation servers to axe-core 4.13. Deque describes this as one of the bigger changes they've made in a few years, so your accessibility issue counts may change.

No rules were added or removed: there are still 105 rules in our axe-core ruleset. What changed is how some existing rules evaluate pages. The release includes 10 false-positive fixes and 13 updates to align axe-core with current web standards.

## Better support for web components One of the biggest changes in axe-core 4.13 is support for Element Internals, a standard way for custom elements to expose accessibility semantics from inside a web component. This matters for component libraries that build custom elements such as ``. With Element Internals, a component can define its ARIA role, accessible name, and other accessibility properties without putting those attributes directly on the element in the DOM. axe-core can now inspect these semantics when testing a page. This means some correctly implemented web components that previously produced false positives can now be evaluated correctly. Deque describes axe-core as the first accessibility testing tool to support this feature. Support isn't universal yet, but sites that make extensive use of custom elements may see noticeable changes in their results. ## Changes that may reduce your issue count Several existing rules have been adjusted to avoid false positives or better match current standards: * [Images must have alternative text](https://rocketvalidator.com/accessibility-validation/axe/4.13/image-alt): whitespace-only `alt` text on presentational images, such as ` `, is no longer flagged. * [Landmarks should have a unique role](https://rocketvalidator.com/accessibility-validation/axe/4.13/landmark-unique): `
` and `
` elements with non-landmark roles are no longer treated as landmarks by this rule. * [ARIA role should be appropriate for the element](https://rocketvalidator.com/accessibility-validation/axe/4.13/aria-allowed-role): roles are now allowed on `` elements that aren't inside a `
` element. * [Elements must only use permitted ARIA attributes](https://rocketvalidator.com/accessibility-validation/axe/4.13/aria-prohibited-attr): many more elements can now have an accessible name. * `aria-actions`, `sectionheader`, and `sectionfooter` are now recognized as valid. * [Elements must only use supported ARIA attributes](https://rocketvalidator.com/accessibility-validation/axe/4.13/aria-allowed-attr): deprecated ARIA attributes such as `aria-grabbed` and `aria-dropeffect` are now reported as [manual review](https://rocketvalidator.com/blog/manual-reviews) items rather than as violations. ## Changes that may increase your issue count Some changes can expose issues that axe-core didn't detect before: * [`role="img"` elements](https://rocketvalidator.com/accessibility-validation/axe/4.13/role-img-alt) and [`` elements with an img role](https://rocketvalidator.com/accessibility-validation/axe/4.13/svg-img-alt) now also recognize `role="image"`, which wasn't covered by these rules previously. * [Elements must only use permitted ARIA attributes](https://rocketvalidator.com/accessibility-validation/axe/4.13/aria-prohibited-attr): `` can no longer be named, so an `aria-label` on a `