I have a Lenovo W530 laptop which I use 90% of the time docked in a lenovo docking station.
All was good with Ubuntu Mate 18.4 LTS. Since I re-installed from scratch Ubuntu Mate 20.4 LTS I have been unable to shutdown/suspend/hibernate the laptop (only when docked) using drop down menu commands. It just goes back to the lightdm login screen and it remains turned on.
To shut it down I must issue a "sudo init 0" command manually from a terminal window. That is the only way it will shutdown.
Is this a known bug?