I have run into this problem as well. The "inactive" in "Turn screen off when inactive for" is a bit misleading: it's not directly about the user being inactive.
For example: Playing an HTML5-YouTube Video in Firefox will delay the turning off of the screen until the video is finished playing. (This is nice, because you don't have to bump the mouse periodically if you're watching a long video.) However, this is not the behavior when playing a Flash-Video in Firefox. In that case, the screen will start turning off when the set timer is expired. My speculation is that Firefox takes some kind of "lock" and prevents Unity from turning off the screen but the Flash-Plugin does not (or Firefox doesn't in that case?) I suspect that after being suspended and resumed a couple of times something goes wrong with this feature (until reboot.) Some application (Firefox in my case probably) does not properly release the "lock" and the screen always stays on. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-screensaver in Ubuntu. https://bugs.launchpad.net/bugs/1594989 Title: Turn off screen after n minutes does not work in Ubuntu 16.04 Status in gnome-screensaver package in Ubuntu: New Bug description: After I upgraded to Ubuntu 16.04, the feature of turning off screen when inactive for a certain period of time, does not work. I have tested it several times, changing the duration, without any avail. This is happening in all the three machines I use. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-screensaver/+bug/1594989/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
