QTableWidget corner button does not select all cells anymore.

#!/usr/bin/env python
import sys
from PySide6.QtWidgets import QApplication, QMainWindow, QTableWidget, QTableWidgetItem
from PySide6.QtCore import QLibraryInfo


class MainWindow(QMainWindow):
    """
    Main window of the application.
    """

    def __init__(self) -> None:
        super(MainWindow, self).__init__()

        # Create QTableWidget
        self.table_widget = QTableWidget(6, 6)
        self.table_widget.setCornerButtonEnabled(True)

        # Populate the table with example data
        for row in range(6):
            for col in range(6):
                self.table_widget.setItem(
                    row, col, QTableWidgetItem(f"Item {row},{col}"))

        # Set the table widget as the central widget of the window
        self.setCentralWidget(self.table_widget)


print('Python {}.{}.{} {}'.format(sys.version_info[0], sys.version_info[1],
                                  sys.version_info[2], sys.platform))
print(QLibraryInfo.build())


app = QApplication([])
window = MainWindow()
window.show()
app.exec()