After
sudo add-apt-repository ppa:kubuntu-ppa/backports
sudo apt-get update
sudo apt-get upgrade
and restarting the computer, I got many problems on KDE (certainly related to the upgrade, maybe related to the kubuntu-ppa/backports):
- Alt+F4 doesn't close windows
- Alt+Tab doesn't switch between windows
- windows' borders, title bar & buttons are not visible
- opened applications don't appear on the Task Manager
- Panel doesn't unhide if a window is maximized
- F2 (rename object) doesn't work in Dolphin
Would you have any idea about how to solve it or, at least, the name of the component that is faulty so I can focus my web searches on it?
Thanks!