Kilotest: Diagnoses of z-index not zero violation by HTML element 204 on Mozilla Foundation page

Here is how tools diagnose the z-index not zero issue for HTML element 204 of the Mozilla Foundation page.

Basics

• About the z-index not zero issue
  • Why it matters: User cannot predict the effect of clicking
  • Priority: lowest
  • Related WCAG standard: 1.4
• About the Mozilla Foundation page
  • URL: https://www.mozilla.org/en-US/
  • Tested on 2026-04-03 at 03:56
• About HTML element 204
  • Take me there
  • Tag name: LI
  • Text: About us
  • Start tag: <li class="m24-c-menu-category mzp-has-drop-down mzp-js-expandable">
  • XPath: /html/body/nav[1]/div[1]/div[1]/div[1]/div[1]/div[1]/ul[1]/li[2]
  • Bounding box: x = 961, y = 16, width = 126, height = 39

Diagnoses

1. z-index style property of the element is 1000

   Tool: Testaro (CVS Health)

   Rule: zIndex