Latop doesn't shutdown when docked into docking station

[Mauro Mozzarelli]

Environment:

Lenovo W530 laptop, docked into Lenovo docking station with external monitor mouse and keyboard
Ubuntu Mate 20.04 LTS

Issue:

I click on the drop down Menu e then select the turn off button.
The computer does not shutdown, the user is logged out, the external monitor goes blank.
Only by opening the laptop lid can I see that the computer is waiting on lightdm login screen.
From lightdm I also try to shutdown using the upper right button, a turn off pop up is shown. Clicking on the on/off button with the mouse the screen button appears to be pressed, but nothing happens.

The only way to shutdown is to login again into a session and issue "sudo init 0" from a terminal window.

The laptop shuts down correctly when used undocked.

[Mauro Mozzarelli (ezplanet1)]

The same laptop/docking/monitor/keyboard configuration behaves correctly when Ubuntu Mate 18.04 LTS is installed

[Mauro Mozzarelli (ezplanet1)]

If I lift the laptop lid (whilst docked) shutdown works normally