Description

While editing the site in full screen and distraction free mode, the header is empty when hovered.

This is only happening in the site editor. Post editor is behaving as expected.

I bisected the behavior change to have been introduced in 3ece636

Step-by-step reproduction instructions

1. Activate Twenty Twenty Four
2. No other plugins
3. Checkout and build commit 3ece636
4. Visit the site editor /wp-admin/site-editor.php?canvas=edit
5. Drag the sidebar away (full-screen mode)
6. Turn on "distraction free" mode
7. Hover over header

Then you can re-build with the parent commit a7a62f7, and it should work as expected.

Screenshots, screen recording, code snippet

Environment info

• WordPress 6.5.2 stable
• Chrome Version 123.0.6312.124 (Official Build) (arm64)
• Gutenberg trunk

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