How to reproduce:
1. Create and open a new blank 3D project
2. Navigate to Window → Package Management → Package Manager
3. Click on the “+“ icon in the top left
4. Select “Install package by name…“
5. In the “Name“ field, enter “com.unity.ai.assistant“
6. In the “Version (optional)“ field, enter “1.5.0-pre.1“
7. Click “Install”
8. After the installation finishes, try moving the GameObjects around in the Hierarchy window

Actual result: The Editor does not allow reordering of the GameObjects
Expected result: You can reorder the GameObjects freely

Reproducible with: 1.5.0-pre.1, 1.5.0-pre.2 (6000.3.7f1, 6000.4.0b7, 6000.5.0a6)
Not reproducible with: 1.0.0-pre.12 (6000.3.7f1, 6000.4.0b7, 6000.5.0a6)

Reproducible on: Ubuntu 22.04
Not reproducible on: macOS 26.2 (M1 Silicon), Windows 11
Could not reproduce on: No other environment tested