keyboard shortcut to lock screen doesn't work on 17.10

[Tessa]

After upgrading to Ubuntu 17.10, the keyboard shortcut to lock the screen (by default, Win-L) doesn't lock the screen anymore. If I go into the keyboard shortcuts settings panel and change it, whatever I change it to does nothing, either. However, the icon in the gnome login menu in the top right does still work, so screen lock isn't entirely broken.

Not sure what component actually controls this, so I'm filing under gnome-shell, since it seems like the thing that'd interpret keyboard hotkeys.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: gnome-shell 3.26.1-0ubuntu4
ProcVersionSignature: Ubuntu 4.13.0-16.19-lowlatency 4.13.4
Uname: Linux 4.13.0-16-lowlatency x86_64
NonfreeKernelModules: zfs zunicode zavl zcommon znvpair
ApportVersion: 2.20.7-0ubuntu3
Architecture: amd64
CurrentDesktop: GNOME
Date: Fri Oct 20 15:59:58 2017
DisplayManager: lightdm
InstallationDate: Installed on 2016-07-08 (468 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to artful on 2017-10-19 (1 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1715435, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.