/usr/share/applications/screensavers/ is in xscreensaver-gl-extra 5.36-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/applications/screensavers/antmaze.desktop
/usr/share/applications/screensavers/atlantis.desktop
/usr/share/applications/screensavers/blocktube.desktop
/usr/share/applications/screensavers/boing.desktop
/usr/share/applications/screensavers/bouncingcow.desktop
/usr/share/applications/screensavers/boxed.desktop
/usr/share/applications/screensavers/cage.desktop
/usr/share/applications/screensavers/carousel.desktop
/usr/share/applications/screensavers/companioncube.desktop
/usr/share/applications/screensavers/crackberg.desktop
/usr/share/applications/screensavers/cube21.desktop
/usr/share/applications/screensavers/cubenetic.desktop
/usr/share/applications/screensavers/cubicgrid.desktop
/usr/share/applications/screensavers/dangerball.desktop
/usr/share/applications/screensavers/extrusion.desktop
/usr/share/applications/screensavers/fliptext.desktop
/usr/share/applications/screensavers/flurry.desktop
/usr/share/applications/screensavers/glhanoi.desktop
/usr/share/applications/screensavers/glplanet.desktop
/usr/share/applications/screensavers/hilbert.desktop
/usr/share/applications/screensavers/hypnowheel.desktop
/usr/share/applications/screensavers/jigsaw.desktop
/usr/share/applications/screensavers/juggler3d.desktop
/usr/share/applications/screensavers/klein.desktop
/usr/share/applications/screensavers/lament.desktop
/usr/share/applications/screensavers/menger.desktop
/usr/share/applications/screensavers/noof.desktop
/usr/share/applications/screensavers/photopile.desktop
/usr/share/applications/screensavers/pinion.desktop
/usr/share/applications/screensavers/providence.desktop
/usr/share/applications/screensavers/rubik.desktop
/usr/share/applications/screensavers/rubikblocks.desktop
/usr/share/applications/screensavers/sballs.desktop
/usr/share/applications/screensavers/skytentacles.desktop
/usr/share/applications/screensavers/sproingies.desktop
/usr/share/applications/screensavers/stairs.desktop
/usr/share/applications/screensavers/starwars.desktop
/usr/share/applications/screensavers/surfaces.desktop
/usr/share/applications/screensavers/tangram.desktop
/usr/share/applications/screensavers/timetunnel.desktop
/usr/share/applications/screensavers/tronbit.desktop
/usr/share/applications/screensavers/unknownpleasures.desktop