Kilotest: Diagnoses of box size absolute violation by HTML element 447 on Mozilla Foundation page

Here is how tools diagnose the box size absolute issue for HTML element 447 of the Mozilla Foundation page.

Basics

• About the box size absolute issue
  • Why it matters: User cannot enlarge the content of an item for readability
  • Priority: high
  • Related WCAG standard: 1.4.4
• About the Mozilla Foundation page
  • URL: https://www.mozilla.org/en-US/
  • Tested on 2026-04-03 at 03:56
• About HTML element 447
  • Tag name: SOURCE
  • Text: [not applicable]
  • Start tag: <source srcset="https://www.mozilla.org/media/img/home/2024/ai-gallery/ventures-desktop-688.920b98ded603.jpg 688w,https://www.mozilla.org/media/img/home/2024/ai-gallery/ventures-desktop-1024.59381046c024.jpg 1024w,https://www.mozilla.org/media/img/home/2024/ai-gallery/ventures-desktop-1360.2dcfd80e7b62.jpg 1360w" sizes="(min-width: 1440px) 680px,calc((100vw - 64px) / 2)" width="1360" height="1088">
  • XPath: /html/body/div[2]/main[1]/section[1]/div[1]/div[1]/div[4]/div[1]/picture[1]/source[2]
  • Bounding box: x = 272, y = 3684, width = 0, height = 0

Diagnoses

1. [failed] The test target `width` attribute uses absolute units.

   Tool: QualWeb (University of Lisbon)

   Rule: QW-BP15