qmlscene does not redraw the items when move the window out of screen and then move back

write a simple qml, for example:

 
import QtQuick 2.0

Rectangle {
  width:200
  height:200
  color:"red"
}

open it with qmlscene, move the whole window out of the screen, and when move it back, the rectangle is not repainted.

This issue seems only happens on Linux and Windows, works fine on Mac OS X.