The key combo was changed to Super+L and it seems to work at least in 18.04 onward.
** Tags removed: artful ** Changed in: gnome-shell (Ubuntu) Status: Incomplete => Fix Released ** Changed in: gnome-settings-daemon (Ubuntu) Status: Incomplete => Fix Released -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/1389650 Title: Ctrl+Alt+L fails to lock the screen in the default setup of Gnome 3 (gnome shell) Status in GNOME Settings Daemon: Confirmed Status in gnome-settings-daemon package in Ubuntu: Fix Released Status in gnome-shell package in Ubuntu: Fix Released Bug description: Ctrl+Alt+L fails to lock the screen in the default setup of Ubuntu 14.10 + Gnome 3 (gnome shell). All packages are up to date and I verified that Ctrl+Alt+L is indeed the shortcut to lock the screen. What helped was adding gnome-screensaver to the startup programs (was installed but wasn't started by default) as mentioned here: http://askubuntu.com/a/542391 To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-settings-daemon/+bug/1389650/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp