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Ubuntu 17.10 (artful) reached end-of-life on July 19, 2018.
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Crash just happened again, right after unlocking screen saver, then the
gnome launcher on the left and status bar at the top disappeared,
followed a few seconds later by Xorg exiting
$ journalctl -t org.gnome.Shell.desktop
-- Logs begin at Wed 2018-03-14 08:38:31 GMT, end at Wed 2018-03-14
