QML: MessageDialog closes on click outside

I'm trying to show an QML MessageDialog with Qt 6.4.3. This dialog should be closed with the provided button.

Here a minimalistic example:

import QtQuick
import QtQuick.Controls
import QtQuick.Dialogs

ApplicationWindow  {
    id: window

    width: 800
    height: 600

    visible: true

    title: qsTr("Hello World")

    Component.onCompleted: dialog.open()

    MessageDialog{
        id: dialog

        modality: Qt.ApplicationModal

        title: "Test Dialog"
        text: "My Text"

        buttons: MessageDialog.Ok
 }

}

PROBLEM: The dialog is dismissed, if the user clickes outside the dialog. I would expect the dialog to stay visible until the user pressed the OK button.

A workaround is to listen to the onRejected signal. But this is not working, if you have a dialog with a CANCEL button.