Comment 6 for bug 205517

In my opinion, the reason for this behaviour is a wrong file association. If you open System Settings and choose "File Associations" from the Advanced tab and look at the entry for text/plain for example (select "Kate" and click on "Edit..."), you will see that the command to open Kate is "/usr/lib/kde4/bin/kate %U". I changed %U into %u, and everything works fine.