I am trying to save a snapshow of a QMainWindow with widgets and title bar.

This is how I tried:

from time import sleep

from PySide6.QtCore import QRect
from PySide6.QtWidgets import QApplication, QMainWindow, QPushButton, QStyle

application = QApplication()
extra_top = application.style().pixelMetric(QStyle.PixelMetric.PM_TitleBarHeight)

button = QPushButton("Hello, world!")

w = QMainWindow()
w.setCentralWidget(button)
w.show()

# Try a bunch of things
w.update()
w.repaint()
w.show()
sleep(0.1)
w.update()
w.repaint()
w.show()
sleep(0.1)

# This snapshot shows the button, but not the title bar
w.grab(
    QRect(
        0,
        -extra_top,
        w.width(),
        w.height() + extra_top,
    )
).save("grabWidget.png")

# This snapshot shows the title bar, but not the button
w.screen().grabWindow(
    w.winId(),
    x=0,
    y=-extra_top,
    w=w.width(),
    h=w.height() + extra_top,
).save("grabWindow.png")

First snapshot:

Second snapshot:

How do I get the best of both?