Window twitching on moving with Quick3D content

ApplicationWindow {
    id: window
    ...

    flags: Qt.Window | Qt.FramelessWindowHint

    Image {
        id: header
        source: "qrc:/images/header.png"
        MouseArea {
            anchors.fill: parent
            property point clickedPos: Qt.point(0, 0)

            onPressed: {
                clickedPos = Qt.point(mouse.x, mouse.y)
            }

            onPositionChanged: {
                var delta = Qt.point(mouse.x - clickedPos.x,
                                     mouse.y - clickedPos.y)
                window.x += delta.x
                window.y += delta.y
            }
        }
    }

    // Just an empty View3D:
    View3D {
        id: view3d
        anchors.fill: parent
    }
}