Robert; the greeter run by lightdm. I was going to do some debugging on it myself today. First time I've installed a Unity desktop in several years so I thought it was intended to ensure the greeter elements were readable on high DPI displays.
Here it's on an Asus T300 Chi with a 2560x1440 display. greeter starts at that resolution then switches to 1280x720 as can be seen in the attached /var/log/lightdm/x-0-greeter.log [+0.59s] DEBUG: main-window.vala:185: Screen is 2560x1440 pixels [+0.59s] DEBUG: main-window.vala:193: Monitor 0 is 2560x1440 pixels at 0,0 [+0.60s] DEBUG: menubar.vala:537: Adding indicator object 0xcfa2e0 at position 2 [+0.60s] DEBUG: Building new application entry: :1.15 with icon: nm-no-connection at position 0 [+0.61s] DEBUG: menubar.vala:537: Adding indicator object 0xf4ae00 at position 3 [+0.63s] DEBUG: menubar.vala:537: Adding indicator object 0xcfa860 at position 2 [+0.64s] DEBUG: unity-greeter.vala:240: starting system-ready sound [+0.66s] DEBUG: background.vala:121: Render of background /usr/share/backgrounds/warty-final-ubuntu.png complete ** (unity-settings-daemon:1279): WARNING **: Unable to register client: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such method 'RegisterClient' [+0.82s] DEBUG: main-window.vala:185: Screen is 1280x720 pixels [+0.82s] DEBUG: main-window.vala:193: Monitor 0 is 1280x720 pixels at 0,0 [+0.86s] DEBUG: background.vala:483: Regenerating backgrounds [+0.86s] DEBUG: background.vala:68: Making background /usr/share/backgrounds/warty-final-ubuntu.png at 1280x720 [+1.02s] DEBUG: background.vala:121: Render of background /usr/share/backgrounds/warty-final-ubuntu.png complete ** Attachment added: "x-0-greeter.log" https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1571640/+attachment/4647722/+files/x-o-greeter.log ** Changed in: lightdm (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1571640 Title: lightdm changing resolution Status in lightdm package in Ubuntu: Confirmed Bug description: Just after the upgrade to ubuntu 16.04, when lightdm starts the resolution is 2560x1600. Then, after about half a second it is automatically changed to 1280x800. This happens systematically at each boot. No external monitor is connected. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.1-0ubuntu1 Uname: Linux 4.5.0-040500-generic x86_64 NonfreeKernelModules: wl ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: Unity Date: Mon Apr 18 14:39:03 2016 EcryptfsInUse: Yes InstallationDate: Installed on 2014-11-09 (525 days ago) InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1) SourcePackage: lightdm UpgradeStatus: Upgraded to xenial on 2016-04-18 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1571640/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
