For example you may have set up only `xscreensaver` to be triggered on login in session autostart. When xfce4-power-manager locks screen before sleep, it starts `xfce4-screensaver`, if it is installed. This is a kind of rebirth of the bug that was reported over 13 years ago: https://bugzilla.xfce.org/show_bug.cgi?id=3770 Use the running screensaver. If `xflock4` script is present (via xfce4-session), you can use that. Tested in: xfce4-session 4.14.2 (Xfce 4.14) xfce4-session has similar issue https://gitlab.xfce.org/xfce/xfce4-session/-/issues/108