unicode-screensaver and gnome-screensaver ========================================= Users of xscreensaver can use the xscreensaver-demo program to configure unicode-screensaver. Users of gnome-screensaver do not have that option. If you use gnome-screensaver and want to change the settings, you have to copy an appropriate .desktop file to: $HOME/.local/share/applications/screensavers/unicode.desktop /usr/share/doc/unicode-screensaver/white-on-black.desktop is such a file which, when moved to $HOME/.local/share/applications/screensavers/unicode.desktop (note that you have to rename the file!) will make the screensaver use white-on-black coloring.