Install gkrellm by entering the following commands in the terminal:
sudo apt update sudo apt install gkrellm
Description:
GNU Krell Monitors
With a single process, gkrellm manages multiple stacked monitors and supports applying themes to match the monitors appearance to your window manager, Gtk, or any other theme.
Homepage: http://gkrellm.net/
Version: 2.3.10-1
Section: universe/x11