For anyone looking for a fix to this issue (Would be nice if Parallels actually fixed the bug)...
Under the VM Configure => Hardware -> Graphics setting:
You CAN NOT set the Graphics option to "Best for Retina display" OR "Best for external displays"
You MUST set it to "Scaled"
After setting to Scaled, it appears to work.
I'm running:
- Parallels Desktop 12 For Mac
- Windows 10 VM
- Two external monitors connected via Thunderbolt
- Separate cable for each monitor, no daisy chaining
Last edited: Dec 19, 2016