SUMMARY Hello everybody, After completing all the available updates yesterday I noticed that suddenly some of the applications, such as krunner wouldn't work anymore and others could not be terminated anymore. As the shutdown app did not work either, I had to use the shutdown terminal command to terminate Kubuntu. When I tried to start up the system, the booting procedure stopped bootsplash and did not go on into the login screen. Watching the booting procedure in the command line mode does not show any errors. After the line saying something like ...user-session... the screen is cleared. Entering the command line mode again, I can login as usual. However, if I try to strart PlasmaShell, I get the following error: ~/kstart5 plasmashell qt.qpa.xcb: could not connect to display qt.qta.plugin: could not load the Qt platform plugin "xcb" in "" even though it was found. This application failed to start because not Qt platform plugin could be initialized. reinstalling the app may fix this problem Available platform plugins are: wayland-org.kde.kwin.qpa, eglfs, ... fish: 'kstart5 plasmashell' terminated by signal SIGABRT (Abbruch) Reinstalling xcb did not fix anything. STEPS TO REPRODUCE 1. Start computer 2. 3. OBSERVED RESULT EXPECTED RESULT SOFTWARE/OS VERSIONS WCurrently running Kubuntu 19.10 plasma-desktop 5.18.0 Qt 5.12.4 KDE Frameworks 5.67.0 Kf5-config 1.0 ADDITIONAL INFORMATION Using startx I get a very basic gnome desktop. starting plasmashell from there works but most of the destop functions are not working. Also, the display configuration in the system settings is not available.
Please try to get a backtrace https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports#Retrieving_a_backtrace_with_GDB
Starting plasmashell from within gdb produces the original error message plus __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50 50 ../sysdeps/unix/sysv/linux/raise.c: Datei oder Verzeichnis nicht gefunden (file or directory not found) I am using the 'Pyramid' global Plasma design.
Almost! You need to type 'bt' into gdb
Sorry, not quite sure how to start 'plasmashell' correctly inside gdb. If I enter (gdb) bt plasmashell I only get a 'No stack'.
>qt.qpa.xcb: could not connect to display that says everything run echo $DISPLAY if that doesn't reply with something like ":0" you have a problem with your env caused by some local changes
There is one other possibility If you've just completed an upgrade your Qt ABI can be out of sync with klauncher. Don't use the kstart5 prefix.
$DISPLAY has got no value.
Set the value to ':0' using echo DISPLAY=:0 but plasmashel still cannot be started and after a reboot the variable is blank again.
Dear Bug Submitter, This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information as soon as possible and set the bug status as REPORTED. Due to regular bug tracker maintenance, if the bug is still in NEEDSINFO status with no change in 30 days the bug will be closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging If you have already provided the requested information, please mark the bug as REPORTED so that the KDE team knows that the bug is ready to be confirmed. Thank you for helping us make KDE software even better for everyone!
After the number of problems increased, I decided to do a fresh install and moved to Neon User Editon, which fixed all issues I had. I am setting the thread to 'resolved' Thanks to eveybody for your support.