Changes/UnfilteredFlathub

Unfiltered Flathub

This is a proposed Change for Fedora Linux.
This document represents a proposed Change. As part of the Changes process, proposals are publicly announced in order to receive community feedback. This proposal will only be implemented if approved by the Fedora Engineering Steering Committee.

Summary

Fedora Workstation's existing third party repo feature allows users to enable a selection of software repos that are hosted by external organizations. This selection has included a filtered version of Flathub since F35, which provides access to a small number of Flathub apps. This change would remove the filtering from our Flathub offering, so that users can enable a complete version of Flathub using the third party repositories feature. In the graphical software manager app, Flathub packages will only be selected by default when no Fedora package is available.

Owner

• Name: Workstation WG
• Email: mclasen@redhat.com

Current status

• Targeted release: Fedora Linux 38
• Last updated: 2023-01-03
• Devel list thread
• FESCo issue: #2828
• Tracker bug: <will be assigned by the Wrangler>
• Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

Since F35, Fedora has included a Flatpak repo definition for Flathub in the fedora-flathub-remote package. This Flathub remote can be used by those who enable third-party software repositories through either GNOME Initial Setup or GNOME Software. Users who do not opt in do not see any content from Flathub.

The current Flathub remote is filtered by an allowlist, to only make a limited subset of software from Flathub available.

The unfiltered Flathub change has two parts:

1. Remove the allowlist from the Flatpak remote, so that when a user opts in, they gain access to all Flathub content and not just a small selection.
2. Adjust GNOME Software so that it uses the following priority order when deciding which package to offer by default:
   1. Fedora Flatpaks
   2. RPMs
   3. Flathub Flatpaks

This will mean that, when using the graphical software manager, Flathub Flatpaks will only be selected by default when there is no Fedora Flatpak or RPM.

Other details:

• In GNOME Software, users will continue to be able to manually select a different source for individual applications.
• The filtering mechanism will remain in place, and it will be possible to reinstate a filter via a package update, should the need arise in the future.
• It has been indicated that it is legally acceptable for us to remove the filtering from the Flathub remote that we make available for users to opt into.
• The UI for enabling the third party repositories clearly states that they contain proprietary software.
• GNOME Software shows information about whether apps are open source or proprietary, so that users can decide whether they want to install them or not.

Feedback

A previous version of this proposal was rejected by FESCo for Fedora 37. It has subsequently been modified to address the concerns raised:

• GNOME Software will prefer packages that have been through the Fedora packaging process, over those that have not.
• For developer tools that do not work well in a sandbox, there will be no Fedora Flatpak, and the RPM will be preferred over the Flathub Flatpak.

Some other questions and concerns that were raised in the previous discussion:

Who owns and runs Flathub?

Flathub is owned and run by the GNOME Foundation, which is a 501c(3) organization registered in the USA. (The GNOME Foundation owns the Flathub trademark, and employs one of the sysadmins who works on Flathub.)

As a non-profit, the GNOME Foundation is required to fulfill a charitable purpose. This is set out in its IRS registration, which states that the organization's mission is "broadening access to technology through the development and distribution of... usable free computer desktop software".

The GNOME Foundation is governed by its Board of Directors, which is elected by contributors to the GNOME project.

Plans exist to create additional governance around Flathub itself, so that other desktops and projects have a formal role in the running of the Flathub service.

Isn't Flathub full of repackaged binaries?

At present, around 10% of the apps on Flathub have been repackaged from another format. These other formats include distro packages and tarballs, as well as binaries. (The previous figure was 12% - the analysis for this can be read here.)

Flathub prefers that apps be built from source, and if sources are available this is what it is expected to be used. Repackaging is only used when sources aren't available, or when it isn't practical to build the entire application, due to size constraints.

But I don't like Flatpak because ___________

Inevitably, people have opinions about the design choices for Flatpak - no technology is ever perfect. Nevertheless, Flatpak is a unique opportunity for Fedora. Some of the key advantages it offers:

• Allows supporting the same app over multiple OS versions
• Is compatible with next-generation image-based operating systems, like Silverblue
• Vibrant upstream application ecosystem, particularly around Flathub
• Distro and platform neutral with no vendor lock-in
• Support for application confinement/sandboxing
• Fully integrated into the GNOME desktop experience

No other application packaging tool has these qualities and, for all these reasons, Flatpak is an important part of the long-term plans for Fedora Workstation.

Lack of community presence around Fedora Flatpaks

We previously received feedback that there were no good contact points for Fedora Flatpaks. The newly created Fedora Flatpak SIG aims to correct this situation, and will be the group that is responsible for Fedora Flatpaks in the future.

The SIG will work to improve the general state of Fedora Flatpaks, including documentation, issue tracking, and coordination.

Benefit to Fedora

Flathub currently hosts nearly 2,000 apps, including many apps which are not included in the Fedora repositories. This includes popular proprietary apps, but also many open source apps which are maintained in Flathub by their developers. This change will make it easier for Fedora users to access this resource.

For users who already use Flathub, this change will make it easier to setup.

Additionally, out of the box application availability is one of the key metrics on which Fedora is judged in comparison to other distros. Having the option to easily enable Flathub will put us in a much more competitive position with regards to our rivals, and will make it easier for people to recommend Fedora as a user friendly Linux distro.

This change will also be a significant improvement over the existing filtered version of Flathub that we offer. This has received a lot of negative feedback, with users being confused by the limited subset of Flathub that are included.

Scope

• Proposal owners:
  • Remove the allowlist in /usr/share/flatpak/fedora-flathub.filter, or replace it with one that allows everything
  • Adjust the name of the remote to reflect its unfiltered nature

• GNOME Software developers:
  • Land this change to fix preference order in g-s: https://gitlab.gnome.org/GNOME/gnome-software/-/merge_requests/1511
  • Make sure that the preference order works as desired on Silverblue as well, where we always want to prefer flatpaks over layering rpms. This is being discussed here: https://github.com/fedora-silverblue/issue-tracker/issues/354

• Release engineering: #Releng issue number
  • No work needed

• Policies and guidelines: N/A (not needed for this Change)
• Trademark approval: N/A (not needed for this Change)
• Alignment with Objectives:

Upgrade/compatibility impact

Existing Fedora installations with a configured Fedora Flathub remote will pick up the new, permissive filter.

How To Test

When third-party software is not enabled in GNOME Initial Setup or GNOME Software, search results from Flathub should not appear in GNOME Software.

When third-party software is enabled in GNOME Initial Setup or GNOME Software:

• Search results from Flathub should appear.
• The default app selected by GNOME Software should be as follows:

Fedora Flatpak?	RPM?	Flathub Flatpak?	Default package
✓	✓	✓	Fedora Flatpak
✗	✓	✓	RPM
✗	✗	✓	Flathub Flatpak
✓	✓	✗	Fedora Flatpak
✓	✗	✗	Fedora Flatpak
✗	✓	✗	RPM

User Experience

When opening GNOME Software after opting into 3rd party software, all the applications that are available on Flathub will show up in search results.

Where there are overlaps, Fedora content will be preferred over Flathub content.

When opening GNOME Software without opting into 3rd party software, only Fedora content will be show up in search results.

Dependencies

No dependencies.

Contingency Plan

• Contingency mechanism: Reinstate the filtering we had in Fedora 36

• Contingency deadline: Beta

• Blocks release? No

Documentation

• fedora-third-party
• Flathub wiki
• Comparison of Fedora Flatpaks and Flathub remotes

Release Notes

The Fedora Flathub remote now exposes all content from Flathub, instead of only a small subset. Flathub is not enabled by default. To enable software from Flathub, turn on third-party software in GNOME Initial Setup or GNOME Software.