System Information
Operating system: Windows 10
Graphics card: Nvidia GeForce GTX 965M
Blender Version
2.80, release candidate 1, blender2.8, 18-07-2019
Short description of error
When trying to select Preferences or Timeline editor with the 3D viewport Pie Menus add-on (Ctrl-Alt-S), the editors don't appear, an error message is displayed, and the data-block menus Scene and View Layer in the top bar disappear.
Exact steps for others to reproduce the error
Based on the default startup: go to Preferences>Add-ons>Pie Menus; enable "3D Viewport Pie Menus" add-on; enable "Editor Switch Pie: Hotkey: Ctrl Alt S"; in any editor, press Ctrl Alt S and select Preferences or Timeline.


