I got the updated through synaptic now and installed it. "System::Administration::Software Sources" now works again, and when launching "gksu --desktop /usr/share/applications/software-properties.desktop /usr/bin/software-properties-gtk" from a terminal no errors at all is printed.
I got the updated through synaptic now and installed it. "System: :Administration ::Software Sources" now works again, and when launching "gksu --desktop /usr/share/ applications/ software- properties. desktop /usr/bin/ software- properties- gtk" from a terminal no errors at all is printed.
Confirming that this bug is indeed fixed.