Install cairo-dock-clipper-plug-in by entering the following commands in the terminal:
sudo apt update sudo apt install cairo-dock-clipper-plug-in
Clipper plug-in for Cairo-dock
A collection of official plug-ins and applets for cairo-dock. . This plug-in keeps a trace of the clipboard and mouse selection, so that you can recall them quickly. It's a clone of the well-know Klipper. This supports clipboard and mouse selection, predefined actions, and persistent items.