so resseting plasma settings could help:
- Log out of KDE.
- Switch to TTY with CTRL + ALT + F2 - if f2 doesnt work, try f1-f6 instead
- Login in TTY with your ‘bad’ account
- Stop the Display Manager service:
sudo systemctl stop display-manager.service
- Run this command to reset the settings:
find $HOME/.config/ -maxdepth 1 -name 'plasma*' -exec rm {} \;
clear cache:
rm -rf ~/.cache/*
- reboot:
systemctl reboot
hopefully this will help, otherwise create the new user, copy browser …etc settings from the old one into the new one…