To reproduce:
1. Open user's attached project
2. Open scene "GIF" under Assets\GIF
3. Enter play mode
4. Make sure Game View tab is visible
5. In the Hierarchy navigate to CameraBse -> Arm -> Main Camera -> RenderComand
6. In the Inspector, tick bool on "Galaxy View" then on "Star Update Voxel" and then once again on "Galaxy View"

--Unity freezes, although the window can be moved, maximized, minimized

Reproduced with: 5.6.3p4, 2017.1.1p2, 2017.2.0f1, 2017.3.0b2

Note: If you drag the Unity window while it is frozen to the other monitor or change its size a few times, the editor crashes. Also, if the Game view is not visible, Unity does not freeze.