Why does "Software Updater" say when performing updates that it is "updating snaps" when in reality it is not?

I always wonder why the Software Updater tool ("update-manager") does say "Updating snaps" for a few seconds after performing package updates when actually it does not do such things.

Instead, after Software Updater is finished, I often enter "sudo snap refresh" in the terminal to find out that there are snap updates available and have them updated. (If I don't do this, snap updates will be installed automatically some time later, but I prefer to get all recent updates before I start working and not while I am working.)

Using Ubuntu 22.04, but it always was the same with 20.04.

I think the "Updating snaps" line is misleading. It's not doing what you think - and not what any reasonable person - would expect.

I took a look at the code for update-manager, and while I'm no developer, I think I understand what's going on.

The code looks like it says "Updating snaps" then proceeds to get a list of snaps which are being migrated from deb to snap - such as lxd, firefox and chromium-browser. It then processes them, if there are any, then moves on. It doesn't process any already-installed snaps, as you might expect.

The message "Updating snaps" should probably be something like "Processing deb to snap migrations" or similar.

Here's the code.

    def update_snaps(self):
        # update status and progress bar
        def update_status(status):
            GLib.idle_add(self.label_details.set_label, status)

        def update_progress(progress_bar):
            progress_bar.pulse()
            return True

        update_status(_("Updating snaps"))

        progress_bar = None
        progress_timer = None

        progress_bars = self.progressbar_slot.get_children()
        if progress_bars and isinstance(progress_bars[0], Gtk.ProgressBar):
            progress_bar = progress_bars[0]
            progress_timer = GLib.timeout_add(100, update_progress,
                                              progress_bar)

        # populate snap_list with deb2snap transitions
        snap_list = self.get_snap_transitions()

        if progress_timer:
            GLib.source_remove(progress_timer)
            progress_bar.set_fraction(0)

        # (un)install (un)seeded snap(s)
        try:
            client = Snapd.Client()
            client.connect_sync()
            index = 0
            count = len(snap_list)
            for snap, snap_object in snap_list.items():
                command = snap_object['command']
                if command == 'refresh':
                    update_status(_("Refreshing %s snap" % snap))
                    client.refresh_sync(snap, snap_object['channel'],
                                        self.update_snap_cb,
                                        progress_callback_data=(index, count,
                                                                progress_bar))
                elif command == 'remove':
                    update_status(_("Removing %s snap" % snap))
                    client.remove_sync(snap, self.update_snap_cb,
                                       progress_callback_data=(index, count,
                                                               progress_bar))
                else:
                    update_status(_("Installing %s snap" % snap))
                    client.install_sync(snap, snap_object['channel'],
                                        self.update_snap_cb,
                                        progress_callback_data=(index, count,
                                                                progress_bar))
                index += 1
        except GLib.Error as e:
            logging.debug("error updating snaps (%s)" % e)
            GLib.idle_add(self.window_main.start_error, False,
                          _("Upgrade only partially completed."),
                          _("An error occurred while updating snaps. "
                            "Please check your network connection."))
            return

        # continue with the rest of the updates
        GLib.idle_add(self.window_main.start_available)