Kilotest: Diagnoses of aria attribute invalid violation by HTML element 230 on Sightline Institute page

Here is how tools diagnose the aria attribute invalid issue for HTML element 230 of the Sightline Institute page.

Basics

• About the aria attribute invalid issue
  • Why it matters: Item behavior violates user expectations
  • Priority: highest
  • Related WCAG standard: 4.1.2
• About the Sightline Institute page
  • URL: https://www.sightline.org/
  • Tested on 2026-04-03 at 04:04
• About HTML element 230
  • Tag name: BUTTON
  • Text: Climate + Energy
  • Start tag: <button class="gb-button gb-button-90781dd5 gb-tabs__button" id="gb-tab-button-90781dd5" aria-controls="gb-tab-item-afb2e4f2" aria-selected="false" tabindex="-1">
  • XPath: [not obtained]
  • Bounding box: x = 708, y = 1196, width = 177, height = 45

Diagnoses

1. The attribute is not allowed for the element on which it is specified

   Tool: Alfa (Siteimprove)

   Rule: r18

2. Elements must only use supported ARIA attributes; ARIA attribute is not allowed: aria-selected="false"

   Tool: Axe (Deque)

   Rule: aria-allowed-attr

3. [failed] The `aria-selected` property is neither inherited nor supported by the `role` button.

   Tool: QualWeb (University of Lisbon)

   Rule: QW-ACT-R25