DragHandler's grab permission CanTakeOverFromAnything does not respect keep grab

#include "ModalLayer.h"
#include <QtDebug>

ModalLayer::ModalLayer(QQuickItem* parent)
    : QQuickItem(parent) {
    this->setAcceptedMouseButtons(Qt::AllButtons);
    this->setAcceptTouchEvents(true);
    this->setKeepMouseGrab(true);
    this->setKeepTouchGrab(true);
}

bool ModalLayer::event(QEvent* event) {
    switch (event->type()) {
    case QEvent::KeyPress:
    case QEvent::MouseMove:
    case QEvent::MouseButtonPress:
    case QEvent::MouseButtonRelease:
    case QEvent::MouseTrackingChange:
    case QEvent::MouseButtonDblClick:
    case QEvent::Wheel:
    case QEvent::TouchBegin:
    case QEvent::TouchUpdate:
    case QEvent::TouchCancel:
    case QEvent::TouchEnd: {
        qDebug() << "BLOCK!" << event->type();
        return true;
    }
    default: break;
    }
    return QQuickItem::event(event);
}

import QtQuick 2.12
import QtQuick.Controls 2.5

import Ui 1.0

ApplicationWindow {
    visible: true
    width: 640
    height: 480

    Rectangle {
        anchors.fill: parent
        color: "grey"

        Rectangle {
            x: 50
            y: 50
            width: 100
            height: 100
            color: "blue"
            DragHandler { }
        }

        Rectangle {
            x: 200
            y: 200
            width: 100
            height: 100
            color: "orange"
            DragHandler {
                grabPermissions: DragHandler.CanTakeOverFromAnything
            }
        }
    }
    ModalLayer {
        anchors.fill: parent

        Rectangle {
            anchors.fill: parent
            color: "red"
            opacity: 0.4
        }
    }
}