Bug#851796: gnome-software: Update don't show up automatically any longer

[Marcus Lundblad]

Package: gnome-software
Version: 3.22.4-1
Severity: important

Before, gnome-software used to show a notification about updates
and when starting it, showing the list of updates available.
But since a while back I have stopped getting these (on both my desktop
machine and laptop).
If I manually run apt update and then start gnome-software, still no
updates are marked (there's no indicator digit in the switcher widget and
no updates in the list), but if I at that point click on the ”Refresh“ button
on the updates page, the list comes up (after searching a while).

Thanks in advance,
Marcus
-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.8.0-2-amd64 (SMP w/8 CPU cores)
Locale: LANG=sv_SE.utf8, LC_CTYPE=sv_SE.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gnome-software depends on:
ii  appstream                                    0.10.5-1
ii  dconf-gsettings-backend [gsettings-backend]  0.26.0-2
ii  gnome-software-common                        3.22.4-1
ii  gsettings-desktop-schemas                    3.22.0-1
ii  libappstream-glib8                           0.6.6-1
ii  libatk1.0-0                                  2.22.0-1
ii  libc6                                        2.24-8
ii  libcairo-gobject2                            1.14.8-1
ii  libcairo2                                    1.14.8-1
ii  libenchant1c2a                               1.6.0-11+b1
ii  libfwupd1                                    0.7.4-2
ii  libgdk-pixbuf2.0-0                           2.36.3-1
ii  libglib2.0-0                                 2.50.2-2
ii  libgnome-desktop-3-12                        3.22.2-1
ii  libgtk-3-0                                   3.22.6-1
ii  libgtkspell3-3-0                             3.0.9-1
ii  libgudev-1.0-0                               230-3
ii  libjson-glib-1.0-0                           1.2.2-1
ii  libpackagekit-glib2-18                       1.1.4-3
ii  libpango-1.0-0                               1.40.3-3
ii  libpangocairo-1.0-0                          1.40.3-3
ii  libpolkit-gobject-1-0                        0.105-17
ii  libsecret-1-0                                0.18.5-2
ii  libsoup2.4-1                                 2.56.0-2
ii  libsqlite3-0                                 3.16.2-1
ii  packagekit                                   1.1.4-3
ii  software-properties-gtk                      0.96.20.2-1

gnome-software recommends no packages.

Versions of packages gnome-software suggests:
pn  fwupd                          <none>
ii  gnome-software-plugin-flatpak  3.22.4-1
pn  gnome-software-plugin-limba    <none>

-- debconf-show failed