Quick Popup wrong reposition

import QtQuick 2.15
import QtQuick.Controls 2.15

ApplicationWindow {
    id: window
    width: 640
    height: 480
    visible: true
    title: qsTr("Stack")

    Dialog {
        id: dialog
        anchors.centerIn: parent
        implicitWidth: 400
        implicitHeight: 100
        enter: Transition {
            // grow_in
            NumberAnimation { property: "scale"; from: 0.1; to: 1.0; easing.type: Easing.OutQuint; duration: 300 }
        }

        exit: Transition {
            // shrink_out
            NumberAnimation { property: "scale"; from: 1.0; to: 0.1; easing.type: Easing.OutQuint; duration: 300 }
        }
        contentItem: Rectangle {
            color: "lightskyblue"
            Text {
                text: "Hello blue sky!"
                color: "navy"
                anchors.centerIn: parent
            }
        }
    }

    Button {
        anchors.centerIn: parent
        text: "Push me"
        onClicked: {
            dialog.open()
        }
    }
}