I installed some special programs a time ago and added several extra repositories. After trying those apps, I uninstalled them and the according repos.
For a several amount of time, I have wierd looking system windows (system settings e.g.). How can I restore the default system apps?
Udate: This is not related to the selected theme. Those themes worked well before, I think, the whole system settings app changed, but I'm not quite sure. If you can compare your for e.g. audio settings tool with mine, you will see a difference.