Crash when print delegateModel of Combobox

// code placeholder
popup: Popup {
        y: control.height - 1
        width: control.width
        implicitHeight: contentItem.implicitHeight
        padding: 1

        contentItem: ListView {
            clip: true
            implicitHeight: contentHeight
            model: control.popup.visible ? control.delegateModel : null
            currentIndex: control.highlightedIndex

            ScrollIndicator.vertical: ScrollIndicator { }
        }

        background: Rectangle {
            border.color: "#21be2b"
            radius: 2
        }
    }

// code placeholder
import QtQuick 2.15
import QtQuick.Window 2.15
import QtQuick.Controls 2.12
Window {
    width: 640
    height: 480
    visible: true
    title: qsTr("Hello World")
    ComboBox {
        id: control
        model: ["First", "Second", "Third"]

        delegate: ItemDelegate {
            width: control.width
            contentItem: Text {
                text: modelData
                color: "red"
                font: control.font
                elide: Text.ElideRight
                verticalAlignment: Text.AlignVCenter
            }
            highlighted: control.highlightedIndex === index
        }



        contentItem: Text {
            leftPadding: 0
            rightPadding: control.indicator.width + control.spacing

            text: control.displayText
            font: control.font
            color: control.pressed ? "#black" : "#red"
            verticalAlignment: Text.AlignVCenter
            elide: Text.ElideRight
        }

        background: Rectangle {
            implicitWidth: 120
            implicitHeight: 50
            border.color: control.pressed ? "#blue" : "#blue"
            border.width: control.visualFocus ? 2 : 1
            radius: 2
        }

        popup: Popup {
            y: control.height - 1
            width: control.width
            implicitHeight: contentItem.implicitHeight
            padding: 1

            contentItem: ListView {
                clip: true
                implicitHeight: contentHeight
                model:  control.delegateModel
                currentIndex: control.highlightedIndex

                ScrollIndicator.vertical: ScrollIndicator { }
            }

            background: Rectangle {
                border.color: "#21be2b"
                radius: 2
            }
        }

    }
    Button{
        x:200
        width: 100
        height: 40
        onClicked: {
            console.log(JSON.stringify(control.delegateModel))
        }
    }
}