Install kdocker by entering the following commands in the terminal:
sudo apt update sudo apt install kdocker
Description:
lets you dock any application into the system tray
KDocker will help you dock any application into the system tray. This means you can dock openoffice, xmms, firefox, thunderbird, anything! Just point and click. Works for all NET WM compliant window managers - that includes KDE, GNOME, Xfce, Fluxbox and many more.
Homepage: https://github.com/user-none/KDocker
Version: 5.0-1
Section: universe/x11