QQuickView::grabWindow() does not work on Mac with Retina Displays?

In my application, a QML script calls a slot of a C++ object that contains a pointer to the QQuickView instance. When the slot is called, the image is grabbed with QQuickView::grabWindow() and then saved as PNG format.

I have attached a screenshot of the original Window content and the result image of QQuickView::grabWindow() in GrabWindowResult.png. It seems the grabbed image is the right dimension, but not capturing the complete Window (probably caused by the retina resolution).

I can provide some code if needed.

Thanks!