Now I'm also noticing that some types are not associated correctly anymore. For example /usr/share/applications/defaults.list contains the entry "application/pdf=evince.desktop" and /usr/share/applications/mimeinfo.cache contains the entry "application/pdf=gimp.desktop;evince-previewer.desktop;evince.desktop;" (both files are readable by my user) but on a double click on a PDF document evince is not started and the context menu doesn't even contain an entry for evince.
Now I'm also noticing that some types are not associated correctly anymore. For example /usr/share/ applications/ defaults. list contains the entry "application/ pdf=evince. desktop" and /usr/share/ applications/ mimeinfo. cache contains the entry "application/ pdf=gimp. desktop; evince- previewer. desktop; evince. desktop; " (both files are readable by my user) but on a double click on a PDF document evince is not started and the context menu doesn't even contain an entry for evince.