login to Kubuntu 18.04 destroys desktop

[marco polo68535]

after login, desktop symbols are at wrong locations, too big and alphabetically sorted instead of the configured locations. the taskbar is missing. the desktop has the wrong wallpaper ("Next von KDE Visual Design Group" instead of "Elarun von Nuno Pinheiro")

problem was introduced through regular updates and occurs in 50% of login cases.

circumvention: kquitapp plasmashell / plasmashell & disown.

then the desktop is back again and correct. remark: we do not to delete or restore datasets plasma-org.kde.plasma.desktop-appletsrc, plasmarc or plasmashellrc.

a cloned system (dd if=/dev/sda of=/dev/sdb) in a Thinkpad T61p (64 Bit) does NOT have the problem.

grub content: GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 nopti nospectre_v1 nospectre_v2 l1tf=off nospec_store_bypass_disable noplymouth"

machine having problem is a Thinpad T60 (32 Bit). system is (cf. "KDE Infozentrum"): Kubuntu 18.04 (last update 14.08.2019) KDE Plasma version 5.12.8 KDE Framwork version 5.44.0 Qt version 5.9.5 Kernelversion 4.15.0.55-generic 32 bit system hardware: 2 x intel cpu T2500 @ 2.00 Ghz memory: 2,0 GB

a new user has the same problem.

we did intensive research and log studies, but no solution was found.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: plasma-workspace 4:5.12.8-0ubuntu0.1
ProcVersionSignature: Ubuntu 4.15.0-60.67-generic 4.15.18
Uname: Linux 4.15.0-60-generic i686
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: i386
CurrentDesktop: KDE
Date: Sat Sep 7 19:03:29 2019
ExecutablePath: /usr/bin/plasmashell
InstallationDate: Installed on 2018-06-03 (461 days ago)
InstallationMedia: Kubuntu 18.04 LTS "Bionic Beaver" - Release i386 (20180426)
SourcePackage: plasma-workspace
UpgradeStatus: No upgrade log present (probably fresh install)

[marco polo68535 (marcopolo68535-deactivatedaccount-deactivatedaccount)]

you can close this bug.

we changed to another hardware (lenovo thinkpad T61p) and the
problem disappears (as mentioned above).

but we are somehow like disappointed, that no one had an idea, what to do.
we would guess, it's a timing problem. sometimes the desktop comes up
correctly. sometimes there is a conflict and sddm is "frightened" and
shows us only the naked standard desktop. but we found never any hint in
syslog, dmesg and other tools and traces.

but this cannot be a normal behavior. the desktop is destroyed every bootup.
we simply managed to do the reconstruction every time by a shell script
(circumvention, see above: kquitapp plasmashell / plasmashell & disown)

[marco polo68535 (marcopolo68535-deactivatedaccount-deactivatedaccount)]

problem has been solved through installation of a new bios
battery (cr 2032) for thinkpad t60.

would be interesting to find out, how this could generate
software problems long (let's say 2 min) after booting
while launching sddm/desktop.