Custom window frame behaving incorrectly on OpenGL Qt build

#include <QtQuick/qquickpainteditem.h>
#include <qapplication.h>
#include <qqmlengine.h>
#include <QtQuick/qquickwindow.h>

class frameLess :
    public QQuickWindow
{
public:
    frameLess(QWindow *parent = 0) :QQuickWindow(parent) { }

    bool nativeEvent(const QByteArray& eventType, void* message, long* result)
    {
        MSG *msg = static_cast<MSG *>(message);

        switch (msg->message)
        {
        case WM_SHOWWINDOW:
            // after that call Qt considers window as frameless
            setFlags(Qt::FramelessWindowHint | Qt::WindowSystemMenuHint | Qt::Window | Qt::WindowMinimizeButtonHint | Qt::WindowMaximizeButtonHint);
            // that call force the Windows to serve users mouse events like in standard window
            SetWindowLongPtr(msg->hwnd, GWL_STYLE, WS_POPUP | WS_CAPTION | WS_THICKFRAME | WS_MAXIMIZEBOX | WS_MINIMIZEBOX);
            return false;

        case WM_NCCALCSIZE:
            // prevent the Windows from painting the frame
            *result = 0;
            return true;

        default:
            break;
        }

        return false;
    }
};

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

    qmlRegisterType<frameLess>("fb", 1, 0, "FrameLess");

    QQmlEngine engine;
    QQmlComponent *component = new QQmlComponent(&engine);

    QObject::connect(&engine, SIGNAL(quit()), QCoreApplication::instance(), SLOT(quit()));

    component->loadUrl(QUrl("qrc:////main.qml"));

    if (!component->isReady())
    {
        qWarning("%s", qPrintable(component->errorString()));
        return -1;
    }

    QObject *topLevel = component->create();
    QQuickWindow *window = qobject_cast<QQuickWindow *>(topLevel);

    QSurfaceFormat surfaceFormat = window->requestedFormat();
    window->setFormat(surfaceFormat);
    window->show();

    return app.exec();
}

import fb 1.0
import QtQuick 2.2
import QtQuick.Controls 1.1

FrameLess {
    color:"lightgray"
    Rectangle {
        width: 45
        height: 45
        color: "green"
        anchors {
            top: parent.top
            left: parent.left
        }

        MouseArea {
            anchors.fill: parent
            hoverEnabled: true;
            onEntered: parent.color="red"
            onExited: parent.color="green"
        }
    }
}