Install XScreenSaver from Ubuntu Repository or PPA
Install xscreensaver from Ubuntu repository with:
#sudo apt install xscreensaver
To install the latest version, you can use the following PPA.
#sudo add-apt-repository ppa:hda-me/xscreensaver
#sudo apt update
#sudo apt install xscreensaver
To check your XScreenSaver version, execute the following command:
#xscreensaver --help