In tandem with efforts moving forward with the ARIA WG, ARIA in HTML is being updated to disallow the use of aria-hidden on the body element.

The intent would be that the same error that the checker already exposes for using aria-hidden=true on the html element would also be raised if the attribute was used on the body element.

We consider this rule already partially supported by this checker, due to the fact that if focusable elements are used on a web page, which would be quite common, that the misuse of aria-hidden is indirectly exposed that way.