Linux: QQuickOverlay geometry is not finalized before Component.onCompleted

import QtQuick
import QtQuick.Controls.Basic

Window {
    id: win
    width: 600
    height: 400
    visible: true

    Overlay.overlay {
        onWidthChanged: console.log("New overlay width:", Overlay.overlay.width)
        onHeightChanged: console.log("New overlay height:", Overlay.overlay.height)
    }

    Component.onCompleted: {
        console.log("At completion...")
        console.log("...the window is visible?", win.visible)
        console.log(`...the window size is ${win.width}x${win.height}`)
        console.log(`...the overlay size is ${Overlay.overlay.width}x${Overlay.overlay.height}`)
    }
}

#include <QGuiApplication>
#include <QQuickWindow>
#include <QTimer>
#include <private/qquickoverlay_p.h>

using namespace Qt::StringLiterals;
using namespace std::chrono_literals;

QQuickWindow *window;
QQuickOverlay *overlay;

static void reportSizes()
{
    qDebug().noquote() <<
            u"Window: %1x%2 Visible?: %3 Exposed?: %4 Overlay: %5x%6"_s
            .arg(window->width())
            .arg(window->height())
            .arg(window->isVisible())
            .arg(window->isExposed())
            .arg(overlay->width())
            .arg(overlay->height());
}

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    QQuickWindow w;
    w.setWidth(600);
    w.setHeight(400);
    w.show();

    window = &w;
    overlay = QQuickOverlay::overlay(window);

    reportSizes();
    QTimer::singleShot(0ms, &app, &reportSizes);
    QTimer::singleShot(10ms, &app, &reportSizes);
    QTimer::singleShot(100ms, &app, &reportSizes);

    return app.exec();
}