[EuiFilterButton] EuiFilterButton should not infer aria-expanded from active filters

[popsiclelmlm]

Reported by

Originally surfaced from Kibana accessibility issue elastic/kibana#227773.

Describe the bug

EuiFilterButton treats hasActiveFilters as a fallback source for aria-expanded when it is rendered as a collapsible chevron button:

const isExpanded = isCollapsible && (isSelected ?? hasActiveFilters);

hasActiveFilters is a visual/filter-count state, not the disclosure open state. A closed filter popover can still have active filters, so this can leave the trigger exposed to assistive technology as expanded even when the controlled popover is closed, or cause a missing false-to-true announcement the next time the trigger opens.

Impact and severity

This affects screen reader users of filter-popover triggers. The Kibana report notes VoiceOver/Safari missing the expanded-state announcement for the Security > Rules > Benchmarks filter buttons. This is WCAG Name, Role, Value related behavior.

Environment and versions

• Kibana version: 9.1.0 in the downstream report
• Browser: Safari 18.5
• Screen reader: VoiceOver
• EUI: current main still has the hasActiveFilters fallback in packages/eui/src/components/filter_group/filter_button.tsx

Minimum reproducible sandbox

A minimal component-level case is a collapsible EuiFilterButton with active filters but no explicit open state:

<EuiFilterButton iconType="chevronSingleDown" hasActiveFilters>
  Status
</EuiFilterButton>

The button receives aria-expanded even though no open/closed disclosure state was provided.

To Reproduce

1. Render EuiFilterButton with iconType="chevronSingleDown" and hasActiveFilters.
2. Do not pass isSelected.
3. Inspect the rendered button.
4. Observe that aria-expanded is derived from active-filter state.

Expected behavior

For collapsible filter buttons, aria-expanded should follow the actual disclosure state supplied through isSelected. hasActiveFilters should continue to affect only active-filter styling and badge semantics. If isSelected is omitted, EUI should not infer a disclosure state from active filters.

Additional context

I have a small local patch with focused RTL coverage that changes the computed expanded state to use isSelected only for collapsible buttons. Happy to open a PR if this scoping looks right.

[JasonStoltz]

Hey @popsiclelmlm, thank you for reporting this. We moved it to our backlog, but I'm not sure when or if we'll address this.

[DevLikhith5]

aria-expanded should only reflect the actual disclosure state (isSelected), not whether the filter has active selections. A closed popover with active filters was incorrectly announcing as expanded.

[github-actions]

👋 Thank you for your suggestion or request! While the EUI team agrees that it's valid, it's unlikely that we will prioritize this issue on our roadmap. We'll leave the issue open if you or anyone else in the community wants to implement it by contributing to EUI. If not, this issue will auto close in one year.

Log | Bot Usage