Operating system: Mojave 10.14.2
Graphics card: Radeon Pro 560
Broken: 2.80 Beta
Short description of error
I was working on a larger monitor attached to my Macbook and removed the HDMI cable from my larger monitor and opened Blender on my laptop monitor only. However the UI wasn't scaling properly and as the video will display the mouse position is functioning but the UI is improperly placed.
Exact steps for others to reproduce the error
As can be seen in the video I just need to launch Blender. I am about to try a system reboot to see if it solves the problem however I can close and open Blender 2.8 as many times as I like and the UI issue is persisting.
Based on the default startup or an attached .blend file (as simple as possible). Any file I open or any way I start Blender 2.8 has this occur.
I hope this is helpful. Thank you very much.
Edit - Upon closing Photoshop Blender rescaled itself to proper screen size and then opened a file I did not select. I will leave this active as I'm not sure the exact cause but it may still be helpful to see or find any potential conflicts.