Workaround for recent XScreenSaver bug #9968

hidden: In which I question this genius solution...

Is it sure that runlevel 3 does not close the xserver?

There is a different work-around to kill screensaver processes. It seems somehow safer…

After that, it is (maybe) necessary to restart screensaver, but it will be better to install the testing version from that thread, to avoid being again locked out.