UI problem when search for block while adding a post

[mai21]

Precondition:

• Gutenberg version 15.9.1
• WP 6.2.2
• PHP 8.2.5
• Ubuntu 23.04

Steps:
1- Create a new post
2- Click the + icon and search for 'block'
3- The UI expands slowly with no interaction

Expected: spaces fit automatically
Screencast: ​https://jmp.sh/KsMTIFiM

[aravindajith]

I conducted testing on different themes to assess the issue's reproducibility. I can confirm that I was able to replicate the problem on some themes, while others remained unaffected.

Themes where I was able to reproduce the issue:

1. TwentyTwenty
2. Twenty Twenty-One
3. OceanWP
4. Kadence
5. GenerateWP

I found that the following themes did not exhibit the reported issue:

1. Twenty Twenty-Two
2. Twenty Twenty-Three
3. Astra
4. Blocksy
5. Spectra One

This discrepancy in behavior across various themes suggests that the issue may be theme-dependent