Extra QColorDialog is painted on parent widget when QColorDialog is moved programmatically

#include <QApplication>
#include <QColorDialog>

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QWidget w;
	w.show();
	
	QColorDialog colorDialog;
	colorDialog.setParent(&w);
	colorDialog.move(100, 200);
	colorDialog.exec();
	
	return a.exec();
}