Screensaver
Replace xscreensaver
with i3lock
[XFCE4][1][?][1] uses /usr/bin/xflock4
to select the screensaver. Uninstall xscreensaver
so we can override it.
Remove xscreensaver
sudo dpkg -r --force-depends xscreensaver
Create /usr/bin/xscreensaver-command
. Prevent a user running it more than once:
!/bin/sh
LOCKER=i3lock
ARGS="-c 103010"
if ! pgrep -u $USER "$LOCKER|$0"
then
$LOCKER $ARGS
fi