Unexpected property value in Repeater in Qt 5.15.2

[RoyG]

The final value of fooProperty seems to depend on whether fooProperty is referenced in onVisibleChanged. Does anyone understand what's leading to this behaviour?

This changed when we upgraded from Qt 5.13 to 5.15.2.

Main.qml

import Qt.labs.platform 1.1
import QtQuick 2.12
import QtQuick.Window 2.3
import QtQuick.Controls 2.5
import QtGraphicalEffects 1.0
import QtQuick.Layouts 1.3

QQuickWindow {
    id: qQuickWindowInstance

    Repeater {
        model: 5

        Item {
            id: fooItem

            FooElement {
                id: fooElementInstance
                fooProperty: index
                fooVisible: true
            }

            Component.onCompleted: {
                // This is supposed to log 0 1 2 3 4, not -1 -1 -1 -1 -1
                // fooProperty doesn't update with value of index if there is an onVisibleChanged function in fooElementInstance that refers to fooProperty
                console.log("Main log fooProperty: ", fooElementInstance.fooProperty)
            }
        }
    }
}

FooElement.qml:

import QtQuick 2.12
import QtGraphicalEffects 1.13
import QtQuick.Controls 2.5

Item {
    id: fooElement
    property int fooProperty: -1
    property alias fooVisible: fooRectangle.visible

    Rectangle {
        id: fooRectangle
        visible: false

        onVisibleChanged: {
            // Comment the below out to have fooProperty take the correct value
            console.log("FooElement log fooProperty: ", fooElement.fooProperty)
        }
    }
}