I tracked my problem down to a bad entry in /usr/local/share/mime/globs (and /usr/local/share/mime/globs2). The application go-gui had registered files of type *.xml to x-go+xml.
I tracked my problem down to a bad entry in /usr/local/ share/mime/ globs (and /usr/local/ share/mime/ globs2) . The application go-gui had registered files of type *.xml to x-go+xml.