Steps to reproduce:

1. Open or create a project
2. Go to "Window" ->"Package Manager"
3. Go to the "My Assets" section
4. If you don't have any assets please download them (for example "Food pack - 3D Microgames Add-Ons")
5. Click on a "+" on the import button
6. Select the imported package item in the list
7. Observe that its details become displayed in the detailed view section
8. Try to resize the window by dragging mentioned section

Expected result: Window UI always should be the same.

Actual result: The window becomes distorted. Added screenshot and video in the "Attachments" section.

Reproducible with: 2023.2.0a23.

Not reproducible with: 2023.1.4f1, 2022.3.4f1, 2021.3.28f1.