Interaction with QML Combobox, makes the application to crash with SEGFAULT on exit.

The issue was identified during development. It was reproduced with the next steps:

1. Create empty QML project
2. import QtQuick.Controls 2.15 and add a Combobox in main.qml (the simple one shown in Qt API reference)

ComboBox {
        width: 200
        model: [ "Banana", "Apple", "Coconut" ]
    }

1. Build and Run on Qt creator
2. If nothing is selected on Combobox, everything goes fine. On terminating the program (either by pressing the x mark on window, or by terminating the execution on Qt creator) nothing strange happens.
3. If Combobox is clicked, no matter if the user selects anything, the program still operates normally. But on program termination (either by pressing the x mark on window, or by terminating the execution on Qt creator) it crashes with segfault.

Notes:

• If QtQuick.Controls 1.4 is imported, the issue doesn't happen.
• Tried a random Combobox from the net (presented bellow), with the original setup (import QtQuick.Controls 2.15), and it didn't crash!!!

ComboBox {
        id: control
        model: 10
        popup: Popup {
            y: control.height - 1
            width: control.width
            implicitHeight: listview.contentHeight
            padding: 1            contentItem: ListView {
                id: listview
                clip: true
                model: control.popup.visible ? control.delegateModel : null
                currentIndex: control.highlightedIndex                ScrollIndicator.vertical: ScrollIndicator { }
            }            background: Rectangle {
                border.color: "#21be2b"
                radius: 2
            }
        }
    }