Dragging the Translation Widget in Perspective Viewport on Mac in a second monitor does not translate the selected Actor

Dragging the Translation Widget in Perspective Viewport on Mac does not translate the selected Actor, and when dragging is released the cursor is moved to the top left corner of the Viewport. Happens consistently with all actors in 4.5.1, and less consistently but still frequently in 4.7.

Only occurs when the editor is in a second monitor.

1. Launch: UE4Editor.app (any project)
2. Move the editor to a second monitor
3. Drop an actor into the level
4. Drag the Widget to translate the actor

Results:
The actor will not move when dragged by the widget. Releasing the widget puts the cursor in the top left corner of the active Viewport.