Wouldn't it be helpful to display at least a short message "Update successful"? Or is that deliberately so ?
Of course is intentional, and it was specifically asked to be like this by some users, that wanted the program to never stop and exit automatically, because they use the updater as part of a batch startup routine, to be sure everything is updated before they start a flight.
Since the same program has a different interface ( the one you start with the "FSDT Installer" ), so you can use that one to be more in control of what is being updated, and it doesn't quit at the end, we listened to the suggestion of making the Update interface running completely automatic, with no confirmation boxes that would stop it.