Screen blink when App go out from full screen in OpenGL

Hello.

I am having trouble when my application goes to full screen and goes out.
I have 3 displays and I am trying to use OpenGL in my application.
For doing this I am using QApplication::setAttribute(Qt::AA_UseOpenGLES, false);
Drivers in my system supports OpenGL ES 2.0 and every thing looks good except when app goes to full screen.

If I use QApplication::setAttribute(Qt::AA_UseOpenGLES, true), it works propertly.
When I select 'false' or comment this line, three of screen suffer of a awful blink when app goes to fulscreen and more than one blinks when app goes out from full screen.

I thought it was a problem of my app, so I have created a small example to prove it:

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C++:

#include <QQmlApplicationEngine>

#include <QtWidgets/QApplication>

#include <QQuickView>

#define QtQuickControlsApplication QApplication

#define qApp (static_cast<QtQuickControlsApplication *>(QtQuickControlsApplication::instance()));

int main(int argc, char *argv[])

{

QtQuickControlsApplication app(argc, argv);

app.setQuitOnLastWindowClosed(true); 

//CHANGE THIS BOOLEAN TO 'FALSE' TO REPRODUCE BLINK WHEN GO OUT FROM FULLSCREEN

bool bANGLE_Active = false;

QtQuickControlsApplication::setAttribute(Qt::AA_UseOpenGLES, bANGLE_Active); 

//show QML

QQmlApplicationEngine* pEngine = new QQmlApplicationEngine();

pEngine->load(QUrl(QStringLiteral("qrc:/resources/ExampleFullScreen.qml"))); 

return app.exec();

}

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QML:

import QtQuick 2.0

import QtQuick.Controls 1.4

import QtQuick.Window 2.2 // Window.FullScreen

import QtQuick.Controls.Styles 1.3

import QtGraphicalEffects 1.0 

ApplicationWindow

{

id: root

objectName: "callToolBar" 

visible: true 

color: "yellow"

height: 140 width: 400 

Rectangle {

anchors.fill: parent color: "red"

} 

// Centered buttons

Row

{

id: buttons 

anchors { bottom: parent.bottom; bottomMargin: 25; horizontalCenter: parent.horizontalCenter } 

visible: true 

width: childrenRect.width

height: 50

spacing: 10 

Button

{

id: button2

text: "Button change visibility"

onClicked: { if(root.visibility !== Window.FullScreen) root.visibility = Window.FullScreen; else root.visibility = Window.Windowed; }

}

}

} 

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If bANGLE_Active = true, it works.
if bANGLE_Active = false it blinks.

Any ideas??