Kilotest: Diagnoses of assertive region not atomic violation by HTML element 254 on Mozilla Foundation page

Basics

About the page

• URL: https://www.mozilla.org/en-US/
• Tested 32 days ago on 2026-09-08 at 04:02 by job 260908T0359-xmh
• Summary of results:
  • Rule engines:
    • Called: 12
    • Were able to test: 12
    • Reported any rule violations: 11
  • Violations: 753
  • Violators: 192
  • Issues: 47
• Download the full technical report (JSON)

About the issue

• Why it matters: User may be unable to get help on what content has changed
• Priority: low
• Related WCAG standard: 4.1.3
• Reported by 1 rule engine (Alfa)
• Violations: 1
• Violators: 1

About the violator

• Tag name: SECTION
• Text: Pause animation … Learn about us
• Start tag: <section class="m24-c-flag" data-animation-running="true">
• XPath: /html/body/div[2]/main[1]/div[1]/section[1]
• Bounding box: x = 240, y = 57, width = 1440, height = 671
• Reported by Alfa

Take me there

Diagnoses

Here is how rule engines diagnose the assertive region not atomic issue for HTML element 254 of the Mozilla Foundation page.

1. The assertive region is not atomic

   Rule engine: Alfa (Siteimprove)

   Rule: r54