Cover Block: Updating a post with a cover block containing a media causes a Problem displaying block

[antonis]

Describe the bug
When a page including a cover block with an image or video is updated a Problem displaying block occurs.

To Reproduce
Steps to reproduce the behavior:

1. Create a post
2. Add a cover block
3. Add an image or video
4. Press Update
5. Notice the Problem displaying block error
6. Close the editor
7. Reopen the page
8. Notice that the block is rendered correctly
9. Edit the block (e.g. add a caption)
10. Press Update
11. Notice the Problem displaying block error

Expected behavior
The cover block should render

Screenshots

cover2.mov

Smartphone (please complete the following information):

• Device: iPhone SE 2020
• OS: iOS 14.2
• Version WP iOS 16.5

Additional context
The problem cannot be reproduced on Android but this is probably due to the fact that the editor closes after an update action

[antonis]

Resolved by an API fix (D55431-code)