Install gnome-applets-data by entering the following commands in the terminal:
sudo apt update sudo apt install gnome-applets-data
Description:
Various applets for the GNOME panel - data files
This package contains data files (pixmaps, icons, documentations) needed by the gnome-applets package.
Homepage: https://wiki.gnome.org/Projects/GnomeApplets
Version: 3.28.0-1
Section: universe/gnome