landmark-unique
Landmarks with the same role must have unique names
Checks that when two or more landmarks share the same role, each has a distinct accessible name.
Applies to. Applies whenever two or more landmark regions on the page share the same landmark role (banner, contentinfo, main, navigation, complementary, region, form, or search; see implementation notes for the detection model).
Expectation. Among landmarks sharing a role, each has a distinct accessible name (via aria-label/aria-labelledby; landmarks are not named from content). Two same-role landmarks with the same name (including two both left unnamed) are indistinguishable to assistive technology users navigating by landmark.
Examples
<nav aria-label="Site">First</nav><nav aria-label="Site">Second</nav>
Two navigation landmarks share the identical accessible name, so a screen reader user can't tell them apart in the landmarks list.
<nav aria-label="Primary">Primary nav</nav><nav aria-label="Footer">Footer nav</nav>
Each navigation landmark has a distinct accessible name.