Comment 13 for bug 1625441

I have a hack workaround working I think. I call a script every minute from a cron job that does something like this:

#!/bin/bash
export DISPLAY=:0
if [ `xprintidle` -gt 240000 ];then
    . ~/.Xdbus
    qdbus org.freedesktop.ScreenSaver /ScreenSaver Lock
fi

The for info about .Xdbus, see:
https://github.com/Jach/cycle_gnome_background