Why it matters
aria-hidden="true" on <body> hides the entire page from screen readers, often left behind by a modal library that failed to clean up.
How to fix it
Remove aria-hidden from <body>. To hide background content behind a dialog, use the inert attribute on sibling containers or a native <dialog>.
References
More accessibility rules
void a11y reports 48 rules in this category. WCAG 2.2 AA through axe-core, plus checks axe can't do alone: visible keyboard focus, 24/44px target size on mobile, 320px reflow and disabled zoom.
aria-rolesInvalid ARIA rolearia-valid-attrInvalid ARIA attribute namearia-valid-attr-valueInvalid ARIA attribute valuearia-hidden-focusFocusable element inside aria-hiddenaria-command-nameARIA button/link/menuitem has no accessible namearia-input-field-nameARIA input field has no accessible namearia-toggle-field-nameARIA toggle has no accessible namearia-prohibited-attrARIA attribute is prohibited for this role