We have several user accounts on the PC and will generally have more than one logged in at any time. Since the last upgrade one of those accounts runs really slowly, so that it is not really possible to use it.
top shows kwin on that account is using much more CPU than on others (about x10).
How could I reset that account to default settings? I suspect there is some setting that is messing it up. I've backed up the home folder and /var/tmp/kdecache-, so can clear those, but doing that gives a mostly blank desktop with nothing to click on.