Summary
Hi! I'm locked out of a linux system running manjaro with plasma due to an error in the login screen, related to wrong plasma settings after an update. I presume the solution is to `chroot` into the system and run some commands to reset plasma settings. Please share ideas on how to reset plasma settings in command line.

Description of issue
When I boot the system, Im greeted with the new KDE login screen. There's an error below the user card. When I enter my password, the screen freezes.

Screenshot of login screen error:
Can be found in this thread
https://forum.manjaro.org/t/system-b...t-boot/31877/7

The error says:
The current theme cannot be loaded due to the errors below, please select another theme. \n file:///user/share/sddm/themes/breath2/Main.qml:26:1: plugin cannot be loaded for module "org.kde.plasma.core": Cannot load library /usr/lib/qt/qml/org/kde/plasma/core/libcorebindingsplugin.so: (/usr/lib/libKF5QuickAddons.so.5: file too short)

This happened after a system update, which suggests the old theme isn't available (or installed) in the new system. I tried `chroot`ing into the system and updating again, but didn't fix it. The solution might be to reset KDE settings while in `chroot`, or some other way to select a new Plasma theme through command line.

I've tried posting this question in the KDE forums but got no answers. I've looked at the KDE documentation, which suggests to delete the /kde4 or /kde folders from home/user/. I did this and didn't solve the issue. Is there some way of resetting plasma themes through command line/ while in `chroot`? Or to make sure plasma dependencies are all met?

Many thanks!

I would try booting to runlevel 3 or bring up a VT at the login screen, and examine/edit /etc/sddm.conf as that is where the current theme is set.

https://wiki.archlinux.org/index.php/SDDM#Current_theme

2 members found this post helpful.

With sddm issues, which is what this sounds like, changes in /home/* should have no impact, as ferrari's answer implies. If the problem is plasma, there are multiple locations for configuration. Often the issue is in the cache, so deleting all or the KDE/Plasma portions of ~/.cache/ could be sufficient. Other KDE/Plasma settings are found in ~/.config/ and ~/.local/share/.

1 members found this post helpful.

It doesn't look like a settings issue to me - it is complaining about a corrupt libKF5QuickAddons.so.5 library, and the solution would be to reinstall or downgrade the package containing this file (libkf5quickaddons5?)

1 members found this post helpful.

I tried several of these things to no avail. Luckily I had a timeshift backup before the my most recent update, and it restored perfectly! Big thanks for your advise!