Bug#975718: gnome-software: Fails to open .deb from Firefox

[Yvan Masson]

Package: gnome-software
Version: 3.38.0-2
Severity: normal

Dear Maintainer,

When downloading a .deb with Firefox, choosing "Open with: 
Gnome-software" (approximate translation), gnome-software fails and show 
this message (in French) "Impossible d'installer : non pris en charge" 
which might be in English "Could not install : not supported".

Journalctl gives a better error:

gnome-software[110920]: failed to convert URL to GsApp: no application 
was created for running url-to-app on plugin=appstream with 
dedupe-flags=7 with 
refine-flags=require-license,require-url,require-size,require-version,require-history,require-setup-action,require-origin,require-related,require-menu-path,require-allow-packages,require-provenance,require-icon,require-permissions,require-origin-hostname,require-runtime,require-screenshots,require-categories,require-project-group,require-developer-name,require-kudos,content-rating 
with timeout=60 with search=file:///tmp/mozilla_yvan0/foo.deb, elapsed 
time since creation 5ms


However, if I download the file in my home directory and then open it 
with gnome-software, it works properly (but unfortunately it does not 
log anything in journald to compare).

Maybe it is a bug from Firefox and not gnome-software… Do not hesitate 
to ask if you need more information or if you want me to report this 
upstream.

Regards,
Yvan

-- System Information:
Debian Release: bullseye/sid
   APT prefers testing
   APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.9.0-1-amd64 (SMP w/4 CPU threads)
Kernel taint flags: TAINT_WARN
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), LANGUAGE 
not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages gnome-software depends on:
ii  appstream                                    0.12.11-1
ii  apt-config-icons                             0.12.11-1
ii  dconf-gsettings-backend [gsettings-backend]  0.38.0-1
ii  gnome-software-common                        3.38.0-2
ii  gsettings-desktop-schemas                    3.38.0-2
ii  libappstream-glib8                           0.7.17-1
ii  libatk1.0-0                                  2.36.0-2
ii  libc6                                        2.31-4
ii  libcairo2                                    1.16.0-4
ii  libfwupd2                                    1.4.6-2
ii  libgdk-pixbuf2.0-0                           2.40.0+dfsg-5
ii  libglib2.0-0                                 2.66.2-1
ii  libgspell-1-2                                1.8.4-1
ii  libgtk-3-0                                   3.24.23-2
ii  libgtk3-perl                                 0.037-1
ii  libgudev-1.0-0                               234-1
ii  libjson-glib-1.0-0                           1.6.0-1
ii  libmalcontent-0-0                            0.9.0-2
ii  libpackagekit-glib2-18                       1.2.1-1
ii  libpolkit-gobject-1-0                        0.105-29
ii  libsoup2.4-1                                 2.72.0-2
ii  libxmlb1                                     0.1.15-2
ii  packagekit                                   1.2.1-1
ii  software-properties-gtk                      0.96.20.2-2.1

Versions of packages gnome-software recommends:
ii  fwupd  1.4.6-2

Versions of packages gnome-software suggests:
pn  apt-config-icons-hidpi         <none>
ii  gnome-software-plugin-flatpak  3.38.0-2
pn  gnome-software-plugin-snap     <none>

-- no debconf information