FFe: Sync gnome-software 46.0-4 (universe) from Debian unstable (main) with gnome-software packaging split

Impact
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I request permission to sync the gnome-software packaging from Debian. The biggest change is splitting gnome-software's .deb support into a separate package, gnome-software-plugin-deb, to match the existing -snap and -flatpak packages. This will allow users and flavors to specifically opt into the parts of the GNOME Software experience they want. For instance, someone may want to use only the Flatpak part because they use the Snap Store to manage .debs and Snaps. Or maybe they want a different combination.

This has been requested by multiple users on Ubuntu Discourse and at least one Launchpad bug and one Debian bug.

fwupd plugin
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I am dropping the fwupd plugin (now in a separate package too) to Suggests so upgrades to Ubuntu 24.04 LTS will likely get it uninstalled and new installs won't have it either unless a user explicitly installs it later.

Ubuntu Desktop includes the firmware-updater snap. Several Ubuntu desktop flavors also include it. For people who don't want snaps, there is also the gnome-firmware app packaged as a .deb.

Because Ubuntu already has update-manager to handle apt update notifications, I am also dropping the autostart file to reduce background RAM use.

A few Ubuntu desktop flavors do not provide any firmware updater app at all. Ubuntu Budgie developers thought a firmware updater app was too technical for inclusion in the default Ubuntu 24.04 LTS install.

autostart
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I have also dropped the autostart file since the fwupd plugin is no longer included by default and Ubuntu already has ways to notify users about available apt updates (update-manager and unattended upgrades) and snaps already automatically update.

Potential Problems
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gnome-software has an explicit Recommend: gnome-software-plugin-deb so that people upgrading to Ubuntu 24.04 LTS will keep the deb support installed. That recommends will be dropped for Ubuntu 26.04 LTS because it won't be needed then. (There is a Depends on the virtual packages that enable installing apps.)

Full Changelog Entries
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gnome-software (46.0-4) unstable; urgency=medium

  * Fix typo in gnome-software-plugin-deb package description
  * Add lintian overrides for desktop-command-not-in-package

 -- Jeremy Bícha Fri, 29 Mar 2024 16:45:30 -0400

gnome-software (46.0-3) unstable; urgency=medium

  * Update Homepage
  * Release to Unstable

 -- Jeremy Bícha Thu, 28 Mar 2024 13:23:28 -0400

gnome-software (46.0-2) experimental; urgency=medium

  * Split deb support into separate gnome-software-plugin-deb package
    (Closes: #1066030) (LP: #2019137, #2056767)
  * Have each plugin provide a virtual gnome-software-plugin package
  * Suggest all the gnome-software plugins
  * Recommend gnome-software-plugin-deb for upgrades
  * Split firmware update support into separate fwupd plugin & recommend it
    except on Ubuntu which provides a separate firmware-updater app
    Intentionally, do not have this provides the virtual gnome-software-plugin
    since it doesn't allow browsing apps.
  * Drop patch that hides upstreams Software Sources dialog (Closes: #1060803)
  * Drop Depends: software-properties-gtk
  * Stop recommending gnome-software-plugin-snap on Ubuntu

 -- Jeremy Bícha Wed, 27 Mar 2024 18:33:03 -0400

Build Logs
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https://launchpad.net/~ubuntu-desktop/+archive/ubuntu/ppa/+sourcepub/15898505/+listing-archive-extra

Desktop Flavors Affected
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GNOME Software is currently included in the default install for only
Ubuntu Cinnamon. See Joshua's comment below.