Reading package lists...
Building dependency tree...
Reading state information...
plasma-desktop is already the newest version.
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 kde-config-gtk-style-preview : Depends: libgtk-3-0 (>= 3.0.0) but it is not going to be installed
 libgtk-3-bin : Depends: libgtk-3-0 (>= 3.14.15-0ubuntu1) but it is not going to be installed
 libscim8c2a : Depends: libgtk-3-0 (>= 3.0.0) but it is not going to be installed