Kubuntu login screen not displayed

[Mike]

Due to more testing i found out that the problem may not be related to sddm. Switching to gdm3 only worked sometimes.

I also found out that detaching one monitor and starting sddm works for me. I can connect the monitor again before loging in and everything is fine.

If i switch to gdm3 i not only need to stop/start the service. I also need to do a dpkg-reconfigure sddm and switch between sddm and gdm3 in order to have it working.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xserver-xorg 1:7.7+13ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-15.31-generic 4.4.6
Uname: Linux 4.4.0-15-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_modeset nvidia
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
CurrentDesktop: KDE
Date: Wed Mar 30 17:51:53 2016
InstallationDate: Installed on 2016-03-26 (4 days ago)
InstallationMedia: Kubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160323)
ProcEnviron:
 LANGUAGE=de
 TERM=xterm
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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