[EuiComboBox] Prevent option title from leaking to list item and keep it on text node

[Copilot]

Summary

This addresses the single review comment on PR #9850: combo box options could still place title on the option <li> via spread props, causing duplicate screen reader announcement paths. The change ensures option-level title is intercepted and applied only to the inner text element.

• What: Updated EuiComboBoxOptionsList to strip title from option rest props before spreading onto EuiListItemLayout, then pass title via textProps only.
• Why: Prevents accessible-description duplication caused by title on the option element while preserving consumer-provided/native truncation tooltip behavior.
• How:
  • Code path updated
    • destructure title: optionTitle from option object
    • compute final title (consumer optionTitle first, truncation fallback second)
    • remove title prop from option <li> and set textProps={{ title }}
  • Regression coverage
    • added focused test asserting:
      • option element does not have title
      • .euiListItemLayout__text does have title

const { title: optionTitle, ...rest } = option;
const title = optionTitle ?? (hasNativeTruncation && !toolTipContent ? label : undefined);

<EuiListItemLayout
  {...rest}
  textProps={{ title }}
/>

API Changes

component / parent	prop / child	change	description
EuiComboBox options	title attribute placement	Changed	title is no longer allowed on option <li> via spread props; it is applied to the inner text element

Screenshots

Before	After
N/A (a11y/DOM attribute placement only)	N/A (a11y/DOM attribute placement only)

Impact Assessment

Note: Most PRs should be tested in Kibana to help gauge their Impact before merging.

• 🔴 Breaking changes — What will break? How many usages in Kibana/Cloud UI are impacted?
• 💅 Visual changes — May impact style overrides; could require visual testing. Explain and estimate impact.
• 🧪 Test impact — DOM-attribute assertions targeting option-level title should target the inner text element instead.
• 🔧 Hard to integrate — If changes require substantial updates to Kibana, please stage the changes and link them here.

Impact level: 🟢 Low

Release Readiness

• Documentation: N/A
• Figma: N/A
• Migration guide: N/A
• Adoption plan (new features): N/A

QA instructions for reviewer

• Open an EuiComboBox with an option that includes title.
• Inspect rendered option (role="option") and confirm it has no title attribute.
• Confirm .euiListItemLayout__text contains the title attribute.
• Confirm tooltip behavior for truncated labels remains present on text hover.

Checklist before marking Ready for Review

• Filled out all sections above
• QA: Tested light/dark modes, high contrast, mobile, Chrome/Safari/Edge/Firefox, keyboard-only, screen reader
• QA: Tested in CodeSandbox and Kibana
• QA: Tested docs changes
• Tests: Added/updated Jest, Cypress, and VRT
• Changelog: Added changelog entry
• Breaking changes: Added breaking change label (if applicable)

Reviewer checklist

• Approved Impact Assessment — Acceptable to merge given the consumer impact.
• Approved Release Readiness — Docs, Figma, and migration info are sufficient to ship.

[elastic-vault-github-plugin-prod]

1 visual difference(s) found - expand to review, then click Approve visual changes to update baselines

euidatagrid (1 difference)

Story	Before	After	Diff
compact desktop

[infra-vault-gh-plugin-prod]

💔 Build Failed

• Buildkite Build
• Commit: 4c3de78
• Documentation website
• Storybook
• ❌ Visual regression tests failed (view diff table)

Failed CI Steps

• 📷 Test visual regression

History

cc @alexwizp @Copilot