KDE-Full not working on Ubuntu24.04

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1

Hello,
I installed KDE-full (SDDM) on an Ubuntu24.04 system. However, the graphical session does not even open (and simply states that something went wrong). I’m trying to understand what the system log is referring to but I cannot grasp whether the origin of the problems is that start org.freedesktop.IBus.session.GNOME.service is not starting properly or that it cannot decipher the display configuration state.
Thanks.

2025-02-21T17:19:42.977023+00:00 ip-172-31-5-250 systemd[1144]: Starting xdg-desktop-portal.service - Portal service...
2025-02-21T17:19:42.989504+00:00 ip-172-31-5-250 systemd[1144]: Started gnome-session-manager@gnome.service - GNOME Session Manager (session: gnome).
2025-02-21T17:19:42.989935+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session-manager.target - GNOME Session Manager is ready.
2025-02-21T17:19:42.989999+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session-initialized.target - GNOME Session is initialized.
2025-02-21T17:19:42.990033+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session-x11-services.target - GNOME session X11 services.
2025-02-21T17:19:42.990062+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session@gnome.target - GNOME Session (session: gnome).
2025-02-21T17:19:42.999420+00:00 ip-172-31-5-250 systemd[1144]: Starting gnome-session-signal-init.service - Signal initialization done to GNOME Session Manager...
2025-02-21T17:19:43.004591+00:00 ip-172-31-5-250 systemd[1144]: Starting org.freedesktop.IBus.session.GNOME.service - IBus Daemon for GNOME...
2025-02-21T17:19:43.006633+00:00 ip-172-31-5-250 gnome-session-binary[1632]: Entering running state
2025-02-21T17:19:43.008192+00:00 ip-172-31-5-250 systemd[1144]: Starting org.gnome.SettingsDaemon.XSettings.service - GNOME XSettings service...
2025-02-21T17:19:43.009170+00:00 ip-172-31-5-250 systemd[1144]: Finished gnome-session-signal-init.service - Signal initialization done to GNOME Session Manager.
2025-02-21T17:19:43.012420+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activating via systemd: service name='org.freedesktop.portal.Documents' unit='xdg-document-portal.service' requested by ':1.39' (uid=1000 pid=1661 comm="/usr/libexec/xdg-desktop-portal" label="unconfined")
2025-02-21T17:19:43.025078+00:00 ip-172-31-5-250 systemd[1144]: Starting xdg-document-portal.service - flatpak document portal service...
2025-02-21T17:19:43.025810+00:00 ip-172-31-5-250 sh[1669]: current session already has an ibus-daemon.
2025-02-21T17:19:43.027540+00:00 ip-172-31-5-250 systemd[1144]: org.freedesktop.IBus.session.GNOME.service: Main process exited, code=exited, status=255/EXCEPTION
2025-02-21T17:19:43.027630+00:00 ip-172-31-5-250 systemd[1144]: org.freedesktop.IBus.session.GNOME.service: Failed with result 'exit-code'.
2025-02-21T17:19:43.027890+00:00 ip-172-31-5-250 systemd[1144]: Failed to start org.freedesktop.IBus.session.GNOME.service - IBus Daemon for GNOME.
2025-02-21T17:19:43.034626+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activating via systemd: service name='org.freedesktop.impl.portal.PermissionStore' unit='xdg-permission-store.service' requested by ':1.41' (uid=1000 pid=1680 comm="/usr/libexec/xdg-document-portal" label="unconfined")
2025-02-21T17:19:43.040915+00:00 ip-172-31-5-250 systemd[1144]: Starting xdg-permission-store.service - sandboxed app permission store...
2025-02-21T17:19:43.045906+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Successfully activated service 'org.freedesktop.impl.portal.PermissionStore'
2025-02-21T17:19:43.046111+00:00 ip-172-31-5-250 systemd[1144]: Started xdg-permission-store.service - sandboxed app permission store.
2025-02-21T17:19:43.047354+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Successfully activated service 'org.freedesktop.portal.Documents'
2025-02-21T17:19:43.047553+00:00 ip-172-31-5-250 systemd[1144]: Started xdg-document-portal.service - flatpak document portal service.
2025-02-21T17:19:43.052026+00:00 ip-172-31-5-250 xdg-document-portal[1680]: Ignoring invalid max threads value 4294967295 > max (100000).
2025-02-21T17:19:43.057064+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activating via systemd: service name='org.freedesktop.impl.portal.desktop.gnome' unit='xdg-desktop-portal-gnome.service' requested by ':1.39' (uid=1000 pid=1661 comm="/usr/libexec/xdg-desktop-portal" label="unconfined")
2025-02-21T17:19:43.169973+00:00 ip-172-31-5-250 gsd-xsettings[1673]: Failed to get current display configuration state: GDBus.Error:org.freedesktop.DBus.Error.NameHasNoOwner: Name "org.gnome.Mutter.DisplayConfig" does not exist
2025-02-21T17:19:43.203089+00:00 ip-172-31-5-250 baloo_file[1620]: Baloo File Indexing has been disabled
2025-02-21T17:19:43.208669+00:00 ip-172-31-5-250 systemd[1144]: Started kde-baloo.service - Baloo File Indexer Daemon.
2025-02-21T17:19:44.399742+00:00 ip-172-31-5-250 systemd[1144]: Started org.gnome.SettingsDaemon.XSettings.service - GNOME XSettings service.
2025-02-21T17:19:44.399830+00:00 ip-172-31-5-250 systemd[1144]: gnome-session-x11-services-ready.target - GNOME session X11 services is inactive.
2025-02-21T17:19:44.399868+00:00 ip-172-31-5-250 systemd[1144]: org.gnome.SettingsDaemon.XSettings.target - GNOME XSettings target is inactive.
2025-02-21T17:19:44.399897+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session.target - GNOME Session.
2025-02-21T17:19:44.399929+00:00 ip-172-31-5-250 systemd[1144]: Reached target gnome-session-x11@gnome.target - GNOME X11 Session (session: gnome).
2025-02-21T17:19:44.399953+00:00 ip-172-31-5-250 systemd[1144]: Reached target graphical-session.target - Current graphical user session.
2025-02-21T17:19:44.405995+00:00 ip-172-31-5-250 systemd[1144]: Starting xdg-desktop-portal-gnome.service - Portal service (GNOME implementation)...
2025-02-21T17:19:44.656525+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Successfully activated service 'org.freedesktop.impl.portal.desktop.gnome'
2025-02-21T17:19:44.656610+00:00 ip-172-31-5-250 systemd[1144]: Started xdg-desktop-portal-gnome.service - Portal service (GNOME implementation).
2025-02-21T17:19:44.675900+00:00 ip-172-31-5-250 rtkit-daemon[1222]: Supervising 0 threads of 0 processes of 0 users.
2025-02-21T17:19:44.676819+00:00 ip-172-31-5-250 rtkit-daemon[1222]: message repeated 2 times: [ Supervising 0 threads of 0 processes of 0 users.]
2025-02-21T17:19:44.677803+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activating via systemd: service name='org.freedesktop.impl.portal.desktop.gtk' unit='xdg-desktop-portal-gtk.service' requested by ':1.39' (uid=1000 pid=1661 comm="/usr/libexec/xdg-desktop-portal" label="unconfined")
2025-02-21T17:19:44.683890+00:00 ip-172-31-5-250 systemd[1144]: Starting xdg-desktop-portal-gtk.service - Portal service (GTK/GNOME implementation)...
2025-02-21T17:19:44.722123+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activating service name='org.gnome.ScreenSaver' requested by ':1.47' (uid=1000 pid=1738 comm="/usr/libexec/xdg-desktop-portal-gtk" label="unconfined")
2025-02-21T17:19:44.724688+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Activated service 'org.gnome.ScreenSaver' failed: Failed to execute program org.gnome.ScreenSaver: No such file or directory
2025-02-21T17:19:44.725095+00:00 ip-172-31-5-250 xdg-desktop-por[1738]: g_dbus_proxy_get_name_owner: assertion 'G_IS_DBUS_PROXY (proxy)' failed
2025-02-21T17:19:44.736473+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Successfully activated service 'org.freedesktop.impl.portal.desktop.gtk'
2025-02-21T17:19:44.736900+00:00 ip-172-31-5-250 systemd[1144]: Started xdg-desktop-portal-gtk.service - Portal service (GTK/GNOME implementation).
2025-02-21T17:19:44.753543+00:00 ip-172-31-5-250 dbus-daemon[1201]: [session uid=1000 pid=1201] Successfully activated service 'org.freedesktop.portal.Desktop'
2025-02-21T17:19:44.754116+00:00 ip-172-31-5-250 systemd[1144]: Started xdg-desktop-portal.service - Portal service.
2025-02-21T17:20:03.459332+00:00 ip-172-31-5-250 systemd[1]: Starting sysstat-collect.service - system activity accounting tool...
2025-02-21T17:20:03.462444+00:00 ip-172-31-5-250 systemd[1]: sysstat-collect.service: Deactivated successfully.
2025-02-21T17:20:03.462622+00:00 ip-172-31-5-250 systemd[1]: Finished sysstat-collect.service - system activity accounting tool.
2

What went wrong is really simple. You installed a full DE ( a complete metapackage for that matter) on an existing DE. Bad idea.

3

@dzon. I had removed the previous installation and dependencies (sudo apt remove ubuntu-desktop -y && sudo apt autoremove) as they were causing other issues. Are you saying that I’d also remove GNOME? Thanks.

4

Yes it is trying to start the gnome.service instead of the KDE you installed. The output you show tells you this with all the gnome this and that contained in the output. There is but a single mention of anything KDE related the file indexer baloo.

Started kde-baloo.service - Baloo File Indexer Daemon.
5

ubuntu-desktop and other similar packages are just meta-packages, and don’t necessarily remove any actual gnome packages when uninstalled.

A better meta-package choice when another full desktop environment is installed imo would be kde-plasma-desktop as it doesn’t depend on all the startup and other services, bits and bobs that kde-full or kubuntu-desktop do.

6

I was able to clean up most everything, reinstall KDE-full, and it seems to be working → Will check everything this evening with more time.

7

Good to see you get it sorted.