It’s very annoying. Does anyone know why this happens?
I installed all new windows updates and videodrivers, but it’s not works.
Thanks.
@southd I have the same problem, if you found out how to fix this please mark as solved and let me know.
So I have that exact same problem. Your screenshots could be mine! I’m running in Windows 10 with Direct X 12. I couldn’t find a way to downgrade and I think Unity was running with DX11.
Right-click on your Unity shortcut and open Properties. In the Target field (under the Shortcut tab) you’ll see the path where you installed Unity in quotation marks. At the end (outside the quotations) add: -force-d3d9
Mine looks like this:
“C:\Program Files\Unity\Editor\Unity.exe” -force-d3d9
This should force Unity to run the editor with Direct X 9 and that seems to solve the problem.
I realise this thread is a few months old by now, but hopefully this should help anyone else googling for the same problem. Good luck! 
I have finally solved the problem, you will never believe the cause of the problem
The reason for this problem is a program called “Nahimic for MSI”
All you need to do is close the damn Nahimic, restart Unity, and it will return to normal
This is fucking ridiculous