Kilotest: Diagnoses of negative text-indent violation by HTML element 1019 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: Helper may hide content from a user
• Priority: high
• Related WCAG standard: 4.1
• Reported by 1 rule engine (ASLint)
• Violations: 18
• Violators: 18

About the violator

• Tag name: A
• Text: Instagram (@firefox)
• Start tag: <a class="instagram" href="https://www.instagram.com/firefox/" data-link-position="footer" data-link-text="Instagram (@firefox)">
• XPath: /html/body/div[2]/footer[1]/div[2]/div[1]/div[1]/div[3]/div[2]/ul[1]/li[2]/a[1]
• Bounding box: x = 1568, y = 7363, width = 24, height = 25
• Reported by ASLint

Take me there

Diagnoses

Here is how rule engines diagnose the negative text-indent issue for HTML element 1019 of the Mozilla Foundation page.

1. CSS technique <code>text-indent: -9999px </code> is used to hide text. However, it causes problems for right-to-left language and also keep focus for screen reader outside of visible area.

   Rule engine: ASLint (eSSENTIAL Accessibility)

   Rule: incorrect_technique_for_hiding_content