fix(conversation-thread): target latest turn on prompt re-entry

[TarunAdobe]

Description

Updates swc-conversation-thread roving focus behavior so newly appended conversation turns become the next tab stop when focus is outside the thread. This lets users submit a prompt, wait for the generated response, and use Shift+Tab from the prompt field to return directly to the newest swc-conversation-turn without focus being moved while they are typing.

Also updates swc-conversation-turn accessibility semantics so the focused host element exposes role="group" and an accessible label such as “User message” or “System message”.

Motivation and context

Roving tabindex made it easy to move between turns with arrow keys, but the active tab stop could stay on a previously focused turn. After submitting a new prompt, Shift+Tab from the prompt field could return to an older turn instead of the newly generated response.

This change keeps focus stable while the user is in the prompt field, but updates the thread’s next re-entry target to the latest appended turn. It also ensures the element receiving roving focus has an accessible role and name.

Related issue(s)

• fixes [Issue Number]

Screenshots (if appropriate)

N/A

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Author's checklist

• I have read the CONTRIBUTING and PULL_REQUESTS documents.
• I have reviewed at the Accessibility Practices for this feature, see: Aria Practices
• I have added automated tests to cover my changes.
• I have included a well-written changeset if my change needs to be published.
• I have included updated documentation if my change required it.

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Reviewer's checklist

• Includes a Github Issue with appropriate flag or Jira ticket number without a link
• Includes thoughtfully written changeset if changes suggested include patch, minor, or major features
• Automated tests cover all use cases and follow best practices for writing
• Validated on all supported browsers
• All VRTs are approved before the author can update Golden Hash

Manual review test cases

• swc-conversation-thread returns to the newest generated turn from the prompt field

  1. Open the Conversation thread full pattern story.
  2. Navigate between swc-conversation-turn elements with ArrowUp and ArrowDown.
  3. Press Tab to move focus to the prompt field.
  4. Submit a new prompt and wait for the generated response.
  5. Press Shift+Tab.
  6. Expect focus to land on the newly generated swc-conversation-turn.

• RTI updates do not steal focus from the prompt field

  1. Open the Conversation thread full pattern story.
  2. Focus the prompt field.
  3. Submit a prompt and keep focus in the prompt area while the response is generated.
  4. Expect focus to remain in the prompt field while the new turn is appended.
  5. Press Shift+Tab.
  6. Expect focus to move to the newest conversation turn.

Device review

• Did it pass in Desktop?
• Did it pass in (emulated) Mobile?
• Did it pass in (emulated) iPad?

Accessibility testing checklist

Required: Complete each applicable item and document your testing steps (replace the placeholders with your component-specific instructions).

• Keyboard (required — document steps below) — What to test for: Focus order is logical; Tab reaches the component and all interactive descendants; Enter/Space activate where appropriate; arrow keys work for tabs, menus, sliders, etc.; no focus traps; Escape dismisses when applicable; focus indicator is visible.

  1. Open the Conversation thread story.
  2. Use Tab to enter the thread and ArrowUp / ArrowDown to move between turns.
  3. Use Home and End to jump to the first and last turn.
  4. Use Tab to move to the prompt field.
  5. Submit a prompt, wait for the response, then press Shift+Tab.
  6. Expect focus to return to the newest generated turn with a visible focus indicator.

• Screen reader (required — document steps below) — What to test for: Role and name are announced correctly; state changes (e.g. expanded, selected) are announced; labels and relationships are clear; no unnecessary or duplicate announcements.

  1. Open the Conversation thread story with a screen reader enabled.
  2. Navigate to a user turn and a system turn.
  3. Expect each focused swc-conversation-turn to expose a group role and an accessible label such as “User message” or “System message”.
  4. Submit a prompt and wait for the generated response.
  5. Press Shift+Tab from the prompt field.
  6. Expect the newly generated turn to receive focus and be announced with its role/name and message content.

[changeset-bot]

⚠️ No Changeset found

Latest commit: cd65117

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