QObject.disconnect() behavior in PySide6

I have the following PySide6 code

import sys
from PySide6.QtWidgets import (QApplication, 
    QWidget, QPushButton, QVBoxLayout, QHBoxLayout,
    QLabel)


class Window(QWidget):
    
    def __init__(self):

        super().__init__()
        
        layout = QVBoxLayout()
        self.setLayout(layout)
        self.conn_count = 0
        
        h_layout1 = QHBoxLayout()
        
        self.button = QPushButton('Click me!')
        self.label = QLabel('Connections: 0')
        
        h_layout1.addWidget(self.button)
        h_layout1.addWidget(self.label)
        
        layout.addLayout(h_layout1)
        
        h_layout2 = QHBoxLayout()
        
        connect_button = QPushButton('Connect')
        connect_button.clicked.connect(self.on_connect_clicked)
        
        disconnect_button = QPushButton('Disconnect')
        disconnect_button.clicked.connect(self.on_disconnect_clicked)
        
        h_layout2.addWidget(connect_button)
        h_layout2.addWidget(disconnect_button)
        
        layout.addLayout(h_layout2)
    
    def on_button_clicked(self):
        print('Button clicked')
        
    def on_connect_clicked(self):
        self.button.clicked.connect(self.on_button_clicked)
        self.conn_count += 1
        self.label.setText('Connections: ' + str(self.conn_count))
        print(self.conn_count)
        
    def on_disconnect_clicked(self):
        self.button.clicked.disconnect(self.on_button_clicked)
        self.conn_count -= 1
        self.label.setText('Connections: ' + str(self.conn_count))
        print(self.conn_count)
   

if __name__ == '__main__':
    
    app = QApplication(sys.argv)

    main_window = Window()
    main_window.show()
    
    sys.exit(app.exec())

It connects/disconnects a button clicked signal with a slot named on_button_clicked on 'Connect' and 'Disconnect' buttons click. Here is the output

1
2
3
4
5
6
7
8
9
10
9
8
...001.py:50: RuntimeWarning: Failed to disconnect (<bound method Window.on_button_clicked of <__main__.Window(0x1db021d9430) at 0x000001DB03DAA100>>) from signal "clicked()".
  self.button.clicked.disconnect(self.on_button_clicked)
7
6
5

which means the first 'Disconnect' click removes one connection but the second click removes all the rest.

The same script with PyQt6 gives

1
2
3
4
5
6
7
8
9
10
9
8
7
6
5
4
3
2
1
0

which means that it removes connections one by one. Python 3.11.9, PySide 6.9.1, Windows 11.

What is the reason for this PySide6 behavior and is it documented/mentioned anywhere?

Edit:

Reported as a bug here

https://bugreports.qt.io/browse/PYSIDE-3190

as per the maintainer comment "To disconnect single connections, use the Connection ID object returned by connect()."

Edit2: Says it has been fixed and will be merged into PySide 6.10. This is actually very nice and kudos to the team.