Description

In the Site editor tabbing away from the preview frame causes an error. I expect it to be error free.

This doesn’t happen in 6.7.1 without Gutenberg plugin. I'm not sure if the latest Gutenberg plugin releases have this issue or not.

Step-by-step reproduction instructions

1. Open the Site editor
2. Tab through the UI until the preview frame is focused
3. Tab again (forward or backward)
4. Note the error in the console

Screenshots, screen recording, code snippet

Environment info

• WP 6.7.1 with Gutenberg plugin at trunk
• Chrome
• macOS

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