Widgets drawn 2x size and position on Retina Mac OSX if initially placed on non-Retina screen

[baekgaard]

Widgets (buttons) are drawn at 2x their (x,y) position and size if the initial application windows is placed on a non-Retina screen on a Mac with a Retina display.

As a work-around, moving the window to the Retina screen fixes this, even if the window is then moved back to the non-Retina screen.

This might be a Qt issue, but needs to be analysed.