Kilotest: Diagnoses of select element invalid violation by HTML element 919 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 cannot properly select among options
• Priority: highest
• Related WCAG standard: 4.1.2
• Reported by 1 rule engine (Html Checker API)
• Violations: 2
• Violators: 2

About the violator

• Tag name: OPTION
• Text: Deutsch
• Start tag: <option value="de">
• XPath: [not obtained]
• Bounding box: [not obtained]
• Reported by Html Checker API

Diagnoses

Here is how rule engines diagnose the select element invalid issue for HTML element 919 of the Mozilla Foundation page.

1. The first child option element of a select element with a required attribute, and without a multiple attribute, and without a size attribute whose value is greater than 1, must have either an empty value attribute, or must have no text content. Consider either adding a placeholder option label, or adding a size attribute with a value equal to the number of option elements.

   Rule engine: Html Checker API (World Wide Web Consortium)