"Alt text" within the Cover Block is not updating

[jromales]

Description

What's currently happening:

• If I create a new post/page, add a Cover block, and insert an image from the Media Library, the existing Alt text is copied over; It will show the same info in the Alt text in Cover block. When I update the Alt text within Media Library, the new Alt text isn't copied over to Alt text field in Cover block; It will still show the old one.

What I expect to happen:

• The Alt text should be synced whenever it's updated whether through the Media Library or through the Cover block settings.

Step-by-step reproduction instructions

1. Enable Gutenberg plugin.
2. Upload an image in the Media Library, edit the image, and add something in the Alt text field.
3. Create a new post or page and add a Cover block.
4. Within that Cover block, insert the image from the Media Library.
5. Hover and select the Cover block from the post/page to see the Alt text field in the block settings.
6. Change the Alt text within Media Library or vice versa.

Screenshots, screen recording, code snippet

Environment info

• WordPress version: 5.8.1
• Gutenberg version: 11.5.1
• Browser: Google Chrome
• Macbook Pro with MacOS Big Sur version 11.5.2

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

No

[glendaviesnz]

Thanks for taking time to outline this issue so clearly. This is actually intended behaviour as explained here.

Because of the reasons outlined in that past comment, and the additional background discussion here and here from the accessibility team, I don't think this decision will be revisited, so closing this issue for now, but feel free to reopen if you want to discuss further.