Post editor 'click below content to focus last block' feature unreliable

[talldan]

Description

The padding underneath the post content that's supposed to be clickable, and results in focusing the last block seems pretty unreliable, especially when visiting an empty post for the first time.

It seems to cause some unwanted side effects, like dropdown menus not closing correctly.

Step-by-step reproduction instructions

1. Create a new post
2. Try clicking the area underneath the first block

Expected: It should focus Actual: Nothing happens

Screenshots, screen recording, code snippet

https://github.com/user-attachments/assets/6453113c-01a0-4c15-8329-9a24a1f54e07

Environment info

Reproduced in Brave and Firefox

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

• [X] Yes

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

• [X] Yes