How to reproduce:
1. Create a new Universal 3D Project
2. Open Package Manager (Window -> Package Manager)
3. Click the "+" icon 
4. Click "Install package from git URL"
5. Type "com.unity.entities@1.3.0-pre.4" and click enter
6. Click the "+" icon again
7. Click "Install package from git URL"
8. Type "com.unity.netcode@1.3.0-pre.4" and click enter
9. After the packages finish installing open Play Mode Tools window (Window -> Multiplayer -> Play Mode Tools)
10. Undock the window if it is docked and try to resize it

Expected result: The window can be resized
Actual result: The window can only be resized vertically and not horizontally

Reproducible with: 1.0.0-exp.8 (2022.3.39f1), 1.3.0-pre.4 (6000.0.12f1)
Not reproducible with: 0.1.0-preview.6 (2020.2.0a5)
Couldn't test with: 0.2.0-preview.5 - 0.51.1-preview.21 (2021.2.0a15) - Unresolvable package errors after installing

Reproduced on: macOS Sonoma 14.5