Individual carousel cards are not narrated by AT when focusing inside the carousel

[corinagum]

Screenshots

Version

4.13.0

Describe the bug

When navigating by keyboard so focus inside a carousel, AT will read buttons, but not read the content of the card.

Steps to reproduce

1. Go to MockBot/playground
2. Turn on AT
3. Type 'carousel'
4. Note that aria-live reads the entire contents of the carousel (expected)
5. Using keyboard, navigate into transcript and focus on carousel attachment (pressing enter to interact)
6. All buttons are focusable (and read aloud), but the card contents are not read. (incorrect)

Expected behavior

When navigating by keyboard, AT should summarize each card when focused, or at least summarize details (aria-details) when focusing on buttons inside the card.

[Bug]