Transient parent of Window is not clear when Loader is involved

import QtQuick 2.0
import QtQuick.Window 2.2

Item {
    width: 400
    height: 400

    // case 1: top level window is transient parent of window 1
//    Window {
//        width: 200
//        height: 200
//        visible: true
//        color: "blue"

//        Text {
//            anchors.centerIn: parent
//            color: "white"
//            text: "Window 1"
//        }
//    }

    // case 2: top level window is *not* transient parent of window 2
    Loader {
        sourceComponent: Window {
            width: 100
            height: 100
            visible: true
            color: "red"

            Text {
                anchors.centerIn: parent
                color: "white"
                text: "Window 2"
            }
        }
    }

    // case 3: top level window is transient parent of window 3
//    Loader {
//        sourceComponent: Item {
//            Window {
//                width: 100
//                height: 100
//                visible: true
//                color: "orange"

//                Text {
//                    anchors.centerIn: parent
//                    color: "white"
//                    text: "Window 3"
//                }
//            }
//        }
//    }
}