Rendering problems when dragging to alternate display

Tor Messenger version 0.1.0b6 for OS X

Start Tor Messenger => "Accounts - Tor Messenger" and "Tor Messenger" windows open (on MacBook Pro Retina 15" 2880x1800 display); rendered as intended.

Drag windows to 2nd display (ASUS ML238 23" 1920x1080) => windows do not redraw properly. Screen grab attached.

Trac:
Username: FrazzleDancer