Blackscreen with Mousecursor visible after login (but works with other user)

Hello everyone, yesterday something really weird happened.

I’m on “ManjaroLinux v.23.1.0”.

I’ve downloaded the latest .Appimage for Ultimaker Cura (hxxps://github.com/Ultimaker/Cura/releases/download/5.6.0/UltiMaker-Cura-5.6.0-linux-X64.AppImage)

and after launching it, Dolphin crashed, followed by KDE Plasma.

I was able to ctrl + alt fX to another session and did a reboot.

From that time on, after I typed my password into the login screen, it starts to load (spinning icon appears) but the white progress bar, which normally follows, did not appear.

Instead it boots to a black screen with the mouse cursor visible.

I ctrl + alt’ed to another session again and did a pacman -Syuu to install the latest updates, still the same issue.

I started seeking through journal ctl and found something AppImage related:

“Scheduling for (re-) Integration: /home/dot/.Xauthority-c”
“Scheduling for unintegration: /home/dot/.Xauthority-c”
“Scheduling for unintegration: /home/dot/.Xauthority-l”
“ERROR: file does not exist, cannot integrate”

Other relevant findings:

“xdg-desktop-portal.service: start operation timed out. Terminating. Failed with result ‘timeout’”

I tried ctrl + alt’ing to another session and typed “startx” as suggested in another thread, which immediately closed after starting.

I noticed that my ~/.xinitrc contained “#DEFAULT_SESSION=startkde” so I replaced that line with “DEFAULT_SESSION=startplasma-x11”. which eventually got me to the same behavior as described above. (Black screen with mouse cursor visible).

In my desperation I created another user with useradd/adduser and tried to log in. It works without any issues.

So I think it’s somehow related to my profile. And here is where I struggle, because I’m not familiar with debugging of the X → KDE → SDDM “cascade”.

I’ve tried to move my ~/.config/plasma-workspace to ~/.config/plasma-workspace.bak and ~/.config to ~/.config.bak with the hopes it won’t pull some problem-related config files, but that did not help at all.

Additional Logs:

journalctl of the blackscreen login:

journalctl of the working login:

I’ve tried running “kbuildsycoca5 --noincremental” from the cli of the broken user:

kbuildsycoca5 running...
terminate called after throwing an instance of 'std::bad_alloc'
  what():  std::bad_alloc

It consumes all available memory (16 GB) and then crashes after that.

Since I cant edit my first post, I’ll reply with a complete update:

Hello everyone, yesterday something really weird happened.

I’ve downloaded the latest .Appimage for Ultimaker Cura
https://github.com/Ultimaker/Cura/releases/download/5.6.0/UltiMaker-Cura-5.6.0-linux-X64.AppImage
but after launching it, Dolphin crashed, followed by KDE Plasma.

I was able to ctrl + alt fX to another session and did a reboot.

From that time on, after I typed my password into the login screen, it starts to load (spinning icon appears) but the white progress bar, which normally follows, did not appear.

Instead it boots to a black screen with the mouse cursor visible.

I ctrl + alt'ed to another session again and did a pacman -Syuu to install the latest updates, still the same issue.

I started seeking through journal ctl and found something AppImage related:

“Scheduling for (re-) Integration: /home/dot/.Xauthority-c”
“Scheduling for unintegration: /home/dot/.Xauthority-c”
“Scheduling for unintegration: /home/dot/.Xauthority-l”
“ERROR: file does not exist, cannot integrate”

Other relevant findings:

xdg-desktop-portal.service: start operation timed out. Terminating. Failed with result 'timeout'

I tried ctrl + alt’ing to another session and typed “startx” as suggested in another thread, which immediately closed after starting.

I noticed that my ~/.xinitrc contained “#DEFAULT_SESSION=startkde” so I replaced that line with “DEFAULT_SESSION=startplasma-x11”. which eventually got me to the same behavior as described above. (Black screen with mouse cursor visible).

In my desperation I created another user with useradd/adduser and tried to log in. It works without any issues.

So I think it’s somehow related to my profile. And here is where I struggle, bc I’m not experienced with the whole X, KDE, SDDM stuff.

What I’ve tried so far:
mv ~/.config/plasma-workspace ~/.config/plasma-workspace.bak
rm -r ~/.cache
mv /etc/X11/xorg.conf /etc/X11/xorg.conf.bak
kbuildsycoca5 --noincremental → consumes all available memeory and crashed with

kbuildsycoca5 running…
terminate called after throwing an instance of ‘std::bad_alloc’
what(): std::bad_alloc

I managed to get the journalctl logs.

For the blackscreen login:

For the sucessful login (newly created user):

From the failed session this got my attention:

Dez 13 14:59:12 dot-pc dbus-daemon[1269]: [session uid=1001 pid=1267] Activating service name=‘org.freedesktop.systemd1’ requested by ‘:1.0’ (uid=1001 pid=1261 comm=“startplasma-x11”)
Dez 13 14:59:12 dot-pc dbus-daemon[1269]: [session uid=1001 pid=1267] Activated service ‘org.freedesktop.systemd1’ failed: Process org.freedesktop.systemd1 exited with status 1

It seems like startplasma-x11 can not be executed succesfully.

Moving ~/.local/share/mime to ~/.local/share/mime.bak/ fixed the blackscreen issue for me.