Mouse hover events are (potentially) unnecessarily being sent to items

import QtQuick 2.0
import QtQuick.Window 2.0

import App 1.0

Window {
    id: root
    width: 640
    height: 480
    visible: true

    property int fps

    PaintedItem {
        anchors.fill: parent

        Rectangle {
            id: rotationItem
            width: 100
            height: 100
            color: "salmon"
            anchors.bottom: parent.bottom

            property int timesUpdated: 0

            NumberAnimation on rotation {
                from: 0
                to: 360
                duration: 500
                loops: Animation.Infinite
            }

            onRotationChanged: ++timesUpdated
        }

        Timer {
            interval: 1000
            repeat: true
            running: true
            onTriggered: {
                root.fps = rotationItem.timesUpdated / (interval / 1000);
                rotationItem.timesUpdated = 0;
            }
        }
    }
}

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQuickItem>

class CustomItem : public QQuickItem
{
    Q_OBJECT

public:
    CustomItem() {
        setAcceptedMouseButtons(Qt::AllButtons);
        setAcceptHoverEvents(true);
    }

    void hoverEnterEvent(QHoverEvent *event) override
    {
        qDebug() << "hoverEnterEvent:" << event;
        QQuickItem::hoverEnterEvent(event);
    }

    void hoverMoveEvent(QHoverEvent *event) override
    {
        qDebug() << "hoverMoveEvent:" << event->posF();
        QQuickItem::hoverMoveEvent(event);
    }

    void hoverLeaveEvent(QHoverEvent *event) override
    {
        qDebug() << "hoverLeaveEvent:" << event;
        QQuickItem::hoverLeaveEvent(event);
    }
};

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

    qmlRegisterType<CustomItem>("App", 1, 0, "CustomItem");

    QQmlApplicationEngine engine;
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

    return app.exec();
}

#include "main.moc"