Install kshutdown by entering the following commands in the terminal:
sudo apt update sudo apt install kshutdown
Description:
advanced shut down utility for KDE
It has 4 main commands: . - Shut Down (logout and halt the system), - Reboot (logout and reboot the system), - Lock Screen (lock the screen using a screen saver), - Logout (end the session and logout the user). . It features time and delay options, command line support, wizard, and sounds.
Homepage: http://kshutdown.sourceforge.net/
Version: 4.2-1
Section: universe/kde