Background
This task covers the broader accessibility review for the new ULS before deployment to production.
The ULS is a global product used across 300+ Wikipedia language editions. As such it is subject to accessibility obligations in multiple jurisdictions, most notably WCAG 2.1 Level AA, which underpins both the European Accessibility Act (in force June 2025) and ADA web accessibility case law in the US. Our understanding is that Wikimedia aims for WCAG AA conformance at minimum.
Known accessibility issues in the current ULS (pre-rewrite)
The following issues are documented and are expected to be addressed by the rewrite:
- Keyboard navigation is unreliable — arrow keys jump unpredictably between columns, page up/down do not work, sometimes typing is the only way to select a language (T309913) — maps to WCAG 2.1 SC 2.1.1 Keyboard
- HTML structure misrepresents item count for screen readers (T282024) — maps to WCAG 2.1 SC 1.3.1 Info and Relationships
- Layout shifts cause wrong clicks — maps to WCAG 2.1 SC 2.5.3 / 3.2.2
- No dark mode support, which affects users with visual impairments relying on dark mode (T363762)
General MediaWiki accessibility context and known gaps are documented at: https://www.mediawiki.org/wiki/Accessibility_and_usability_cleanup
Relevant developer reference is: https://www.mediawiki.org/wiki/Accessibility_guide_for_developers
The full WCAG 2.2 success criteria are at: https://www.w3.org/TR/WCAG22/
Goal
Perform an accessibility review of the new ULS component before deployment to production, confirm that known issues are resolved, and ensure the new implementation meets WCAG 2.1 Level AA conformance.
Scope
- New Universal Language Selector component (content language selector and interface language selector)
- All entry points that will be live at time of deployment
- Desktop and mobile
- Dark mode
What we don't know yet
- Who will conduct the review
- What tooling and methodology will be used (automated testing and/or manual testing)
- Whether we need a formal audit report for compliance purposes or an internal review is sufficient
- Timeline: target is before deployment
Next steps
- Confirm reviewer and methodology
- Define what "passed" looks like: full WCAG 2.1 AA audit or targeted review of known issues
- Coordinate with @bwang (has expressed interest in supporting this)
Related tasks
- T282024: ULS language list should use `column-width` CSS property instead of splitting the lists
- T309913: ULS language selector can't be navigated using the keyboard
- T363762: ULS should eliminate references to the "legacy" Codex design tokens
- T314620: The Language selector appears on pages where it is not used
- T119342: Accessibility of ULS language selector on mobile
- T325008: Chinese, Korean, and Russian menu items in Language menu not spoken by NVDA
- T431255: ULS rewrite shouldn’t override text-decoration property