If the VSDecoder user hits the Save to Roster button on the VSDecoder GUI, it modifies the roster in memory, but does not save those changes to file. The user must then Edit the RosterEntry and explicitly save the changes to file.
Not sure best way to fix this. The user could be editing the roster in a way that they don't want saved, so saving directly to file might have some unintended consequences. Perhaps pop an "are you sure" dialog before saving to file, maybe if I can tell that the roster is otherwise "dirty" THEN post the dialog.