Lockscreen doesn't turn off the screen

[sds]

precisely as in https://bugs.launchpad.net/ubuntu/+source/gnome-screensaver/+bug/1292041:

Ctrl-Alt-L locks the screen but it is never turned off.
Also, after the default delay (5 min) the screen is locked but not turned off.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: gnome-screensaver 3.6.1-7ubuntu1
ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6
Uname: Linux 4.2.0-19-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Thu Nov 26 11:05:18 2015
GnomeSessionIdleInhibited: No
GnomeSessionInhibitors: None
GsettingsGnomeSession:
 org.gnome.desktop.session session-name 'ubuntu'
 org.gnome.desktop.session idle-delay uint32 600
SourcePackage: gnome-screensaver
UpgradeStatus: Upgraded to wily on 2015-10-25 (32 days ago)

[Sebastien Bacher (seb128)]

Thank you for your bug report, are you really using gnome-screensaver or are you using unity and its standard lock screen?

[sds (sds-gnu)]

I am using unity.
I don't know what specific program is responsible for turning the screen off.
`ps` seems to indicate that `gnome-screensaver` is not running, although the package is installed.
I just uninstalled the package and the behavior did not change.
I guess this is a bug in unity then.

[Launchpad Janitor (janitor)]

[Expired for gnome-screensaver (Ubuntu) because there has been no activity for 60 days.]