Hello everyone,

I'm having trouble starting KDE, plasmashell ends up in "stopped" state, leaving a blank desktop. No wallpaper, no panel etc are not shown. (kwin still work fine and the desktop menu with right click).

If I get out of session and log in again, everything works.
I think it's a known bug that can be seen here:
https://bugs.kde.org/show_bug.cgi?id=361166

I did a clean install today and the problem recurs. The same applies to new users in the system.

Anyone else experienced this?

The bug you linked was fixed months ago.
Do you have the same settings as in that report? (not sorting set in task manager), what task manager in use? Default icons only task-manager, or some changed settings?
Did you have the crashes right away in live mode? Right after first boot into the new install?
If not, what did you change?

Best post the output link of Octopi > tools > SysInfo
Also post your /etc/sddm.conf

I have no problems in live mode. I also had no problems after installation.
The task manager does not appear, because there is no panel. Added via widget, works normal.

My SysInfo
https://gist.github.com/anonymous/d9a30fd6ce033258bc3463ba9350ef9b

I had the problem before installing most of the program. I add some widgets and open programs for research of plasma.
It always happens after the first boot. If I log out and back, the settings, paper looks and everything else work.

My sddm/xorg-session.log (shows errors)
https://gist.github.com/anonymous/16de6f514175cba9970c629917055f23

My /etc/sddm.conf
https://gist.github.com/anonymous/65fef239eb88fa0849a880786dac38c8

Maybe those in errata https://community.kde.org/Plasma/5.7_Errata I have skylake and i don't have problems with sna but you may experience them. You can try Xorg drivers instead provided by Intel.

cat << EOF | sudo tee /etc/X11/xorg.conf.d/20-intel.conf
Section "Device"
    Identifier "Intel"
    Driver "modesetting"
    Option "AccelMethod" "glamor"
    Option "Backlight" "intel_backlight"
EndSection
EOF

Logout/in, if you have problems just type alt+ctrl+f2, login in new tty

sudo rm -f /etc/X11/xorg.conf.d/20-intel.conf
sudo systemctl restart sddm.service

When do you start having this issue? Maybe after install plank?? I really don't know so much on this theme, but if you have tried with the answer of bvbfan, and that doesn't work, you can try removing plank and its dependencies, especially libdbusmenu-gtk... And if that doesn't work, posting the output of running plasmashell on a terminal.

Since no such issue in live mode or fresh install, you can pretty much eliminate drivers issue.
Since sddm shows tons of gtk errors, all points to your non repo packages (see the SysInfo log, or run pacman -Qm), remove all those first.

If you do need an alternative task-manager/launcher, try now-dock first.

Thank you all for the comments.

I think I understand what happened! But first, to document, I will relate what I did.

@bvbfan I did what you suggested, but it did not work. In fact it worsened, but when you restart the session can not retrieve the settings. Undid and went back to square one.

@loopset set the problem before I install Plank. But following the advice demm, removed all packages that pecmam -Qm command returned.

bamf 0.5.1-1
franz 4.0.4-1
libdbusmenu-glib 12.10.2-1
libdbusmenu-gtk3 12.10.2-1
libgee 0.18.0-1
libgtop 2.30.0-1
libwnck3 3.4.9-1
plank 0.11.2-1

@demm also tried the now-dock, but work did not show the following error:

Ocorreu um erro ao carregar o arquivo QML: 
file:///usr/share/plasma/plasmoids/org.kdelook.nowdock/contents/ui/main.qml:127:9: Cannot assign to non-existent property "screen"

Dock is not something essential for me. I decided to create a new panel, centralizei and just added the task manager only icons. It works as well as a dock.

The problem continued.... But I found the following...

There is information that I did not say, thinking no relevance. Use a notebook with external monitor connected to VGA, because the LCD screen has deadline problems. This LCD screen is physically removed, but for some reason it is still detected. In the display settings I just let the VGA enabled. This worked for months, but for some reason Kaos even with deactivated LCD and VGA chewed as the primary monitor, played the main screen for the LCD, which did not exist! To prove this theory, I plugged the LCD, even defective, and started the system. To my surprise, the elements, wallpaper, panel and all, appeared on the LCD screen and VGA only a second screen, even with the settings to the contrary. For some reason, when I get out of session and come back, the system returns to recognize the settings normally.

Not to mix the issues will open another topic specific to the case. I think I can rule out any problem in Plasma or KDE at this time.

Thank you all here!

Not really related, but try now-dock 0.3.0, it should be fixed now for plasma 5.8