Install aosd-cat by entering the following commands in the terminal:
sudo apt update sudo apt install aosd-cat
Description:
an on screen display tool which uses libaosd
aosd_cat is an advanced on screen display tool based on libaosd. It can be used for OSD-style notifications in shell scripts.
Homepage: http://www.atheme.org/project/libaosd
Version: 0.2.7-1.1ubuntu2
Section: universe/x11