$ dpkg -l '*xscreensaver*'
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                       Version                    Architecture               Description
+++-==========================================-==========================-==========================-=========================================================================================
ii  xscreensaver                               5.30-1+b1                  amd64                      Screensaver daemon and frontend for X11
ii  xscreensaver-data                          5.30-1+b1                  amd64                      Screen saver modules for screensaver frontends
ii  xscreensaver-data-extra                    5.30-1+b1                  amd64                      Extra screen saver modules for screensaver frontends
ii  xscreensaver-gl                            5.30-1+b1                  amd64                      GL(Mesa) screen saver modules for screensaver frontends
ii  xscreensaver-gl-extra                      5.30-1+b1                  amd64                      Extra GL(Mesa) screen saver modules for screensaver frontends
un  xscreensaver-gnome                         <none>                     <none>                     (no description available)
un  xscreensaver-nognome                       <none>                     <none>                     (no description available)

USING KDE
       Like GNOME, KDE also decided to invent their own screen saver framework from scratch instead of simply using xscreensaver.  To replace the KDE screen saver  with  xscreensaver,  do
       the following:

           1: Turn off KDE's screen saver.
              Open the "Control Center" and select the "Appearance & Themes / Screensaver" page.  Un-check "Start Automatically".

           2: Find your Autostart directory.
              Open the "System Administration / Paths" page, and see what your "Autostart path" is set to: it will probably be ~/.kde/Autostart/ or something similar.

           3: Make xscreensaver be an Autostart program.
              Create a .desktop file in your autostart directory called xscreensaver.desktop that contains the following five lines:

              [Desktop Entry]
              Exec=xscreensaver
              Name=XScreenSaver
              Type=Application
              X-KDE-StartupNotify=false

           4: Make the various "lock session" buttons call xscreensaver.
              The  file  you  want  to  replace  next  has moved around over the years. It might be called /usr/libexec/kde4/kscreenlocker, or it might be called "kdesktop_lock" or "krun
              ner_lock" or "kscreenlocker_greet", and it might be in /usr/lib/kde4/libexec/ or in /usr/kde/3.5/bin/ or even in /usr/bin/, depending on the distro and phase  of  the  moon.
              Replace the contents of that file with these two lines:

              #!/bin/sh
              xscreensaver-command -lock

              Make sure the file is executable (chmod a+x).

       Now use xscreensaver normally, controlling it via the usual xscreensaver-demo(1) and xscreensaver-command(1) mechanisms.