Description

When collaborating in RTC using blocks that contain multiple RichText fields (such as the Quote or Pullquote blocks), making text selections or edits in a secondary field (like citation) causes the cursor to be shown in wrong position in other clients.

From what I can notice, the cursor is off by exactly the length of the first attribute.

Step-by-step reproduction instructions

1. Open a collaborative session with two users (User A and User B).
2. Insert a Quote block.
3. Set the value (quote body) to: hello
4. Set the citation to: testing
5. Have User A place their cursor at the very end of the citation: testing|
6. Look at User B's screen. User A's remote cursor will be rendered at 5 places (length of “hello”) behind the actual position: te|sting.

Screenshots, screen recording, code snippet

This can be reproduced on other multi-attribute blocks like "File" and "Pull Quote" as well.

Environment info

• WordPress: 7.1-alpha-62191
• Gutenberg (23.0.0)
• Chrome on MacOS 26.4

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

• Yes

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

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure