Lockscreen timeout un-blanks the screen

[Doug Smythies]

Just to separate the variables, use a different "Turn screen off when inactive for" time and "Lock screen after" time under "Brightness and Lock" under "System Setting".

Leave the system inactive.
The screen goes blank after the appropriate inactive period.
After the additional screen lock time (or immediately if it is set to "When Screen turns off"), the screen turns back on and stays on, forever.
However, just move the mouse and then the screen will blank after the appropriate inactive period, and this time, and subsequent times, it will stay off.
Now, unlock the computer, and this whole sequence will repeat.

I'm told this is not the same as bug 1292041 ,but I think it is related. Why? Because this issue started the same day as that bug, namely 2014.03.12 (March 12th 2014).

This issue is repeatable on: Ubuntu desktop 14.04; Ubuntu desktop 15.04, as upgraded from previous; Ubuntu desktop 15.04, as newly installed, albeit during development.

This issue does not occur with Ubuntu desktop 12.04. And did not occur with desktop 14.04 development prior to 2014.03.12.

Note: All of my work is with Virtual Computer guests on an Ubuntu server 14.04 host.

doug@desk-ss:~$ lsb_release -rd
Description: Ubuntu 15.04
Release: 15.04
unity 7.3.2+15.04.20150420-0ubuntu1

doug@desk-dev:~$ lsb_release -rd
Description: Ubuntu 15.04
Release: 15.04
unity 7.3.2+15.04.20150420-0ubuntu1

doug@desk-tt:~$ lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04
unity 7.2.4+14.04.20141217-0ubuntu1

doug@desk-pp:~$ lsb_release -rd
Description: Ubuntu 12.04.5 LTS
Release: 12.04
unity 5.20.0-0ubuntu3

[Launchpad Janitor (janitor)]

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

[Alex D (iueoqre)]

I can confirm this is still the case in 15.10.

[Doug Smythies (dsmythies)]

Issue persists with 16.04.

I never had a physical (not VM) desktop before, but I do now. The issue does not occur on it.