How to save screenshot?

Hi, im on Linux, and Im trying to save a screenshot.
I read that QPixmap::grabWindow() is deprecated, and that I should use QScreen::grabWindow() instead.
So I did.
The problem is: The image is not being saved right, and does not show up the correct part of screen (only 4 parts of screen, upside down and in all kind of ways).

This ma code.

Code:

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void Widget::on_pushButton_clicked()
{
    QScreen *QSCREEN = QGuiApplication::primaryScreen();
    QPixmap qpix = QSCREEN->grabWindow(this->winId(), 0, 0, QApplication::desktop()->width(),
                  QApplication::desktop()->height());
    qpix.save("/home/marcus/Bilder/Hello.png");
}

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Code:

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void shootScreen()
{
    QPixmap originalPixmap; // clear image for low memory situations
 
     originalPixmap = QPixmap::grabWidget(tabWidget->currentWidget());    //<== some widget
 
      QString format = "png";
 
      QString fileName = "myshot.png";
 
      originalPixmap.save(fileName, format.toAscii());
 
}

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