GNOME 46 puts Flatpaks front and center

The GNOME project announced GNOME 46 (code-named "Kathmandu") on March 20. The release has quite a few updates and improvements across user applications, developer tools, and under the hood. One thing stood out while looking over this release—a major emphasis on Flatpaks as the way to acquire and update GNOME software.

Improvements

One of the headline features for GNOME 46 is its global search feature, but it requires some tweaking before it becomes as useful as it could be. Users can now bring up the global search by pressing the Super key (the key with a Windows symbol on many keyboards), Ctrl+Shift+F, or by clicking the Activities button in the top bar, provide a search term and the global search feature will display results from installed applications, GNOME's settings, installable applications in the software store, contacts in the GNOME address book, and any matching files. Well, any matching files that are in directories that GNOME has been configured to search.

Weirdly, search is only set up to look through a handful of directories by default, which is not quite what one would expect. A user would likely expect all of the files in their home directory to be part of a global search, but this is not the case. GNOME will search a user's home directory at the top level, plus Documents, Downloads, Music, Pictures, and Videos. If one wants GNOME to search, say, ~/src, then it's necessary to add ~/src specifically as a search location. Once configured to peek into the proper directories, search works quickly and well, but it's not intuitive to have to specify each subdirectory.

The project has also refactored Files (or Nautilus, as it used to be known) to improve performance. (An example of that work is here.) Prior to GNOME 46, Files would be noticeably slow when viewing a directory with, say, a lot of photos. For example, I have one directory with 1,188 JPEGs, a total of 9.8GB of photos. It would take Files quite a while to render the thumbnails for the images, which felt sluggish. Not unusable, but definitely slow even on a recent system with an NVMe drive and 64GB of RAM. Using Files with the improvements in this release feels much faster.

Touchpad settings have gotten a few new options that may make laptop users happy. One of the worst things about early touchpad use on Linux was accidentally sending the pointer skidding across the desktop while typing, and possibly switching application focus accidentally. A setting was eventually added to disable the touchpad while typing, which makes it much easier to write while sitting on the couch. But, some applications call for a combination of key presses and touchpad movement—so users can now turn that feature off if needed.

The touchpad settings also picked up new options for right-clicking (also called "secondary click"), so users can choose whether they prefer to cause a right-click with two fingers or by tapping a corner of the touchpad.

One of the ways GNOME tries to simplify life for users is by providing an easy way to connect to online services, and to share those connections with its applications. For example, users can provide access to a Google account to give GNOME's applications access to Gmail, Google Calendar, and files stored in Google Drive. Users set up access to these services using the online accounts settings. The supported account types have changed over time, but recent releases include support for email (SMTP/IMAP), Nextcloud, Google accounts, Microsoft Exchange, and Kerberos login.

GNOME 46 has added support for Microsoft OneDrive file storage, and support for the WebDAV (file access), CalDAV (calendar), and CardDAV (contacts) protocols. If users connect to a Microsoft 365 account, they will now see files stored in OneDrive in the files application as if they were local files and directories. Unfortunately, I had no success in setting up a connection to any of Fastmail's WebDAV, CalDAV, or CardDAV services.

Showcasing Flatpak

On top of the default applications included with a standard GNOME install, the project has a showcase of applications called GNOME Circle. There are several new applications in the Circle for GNOME 46. These new applications include a lightweight to-do application called Errands, a minimal audio player called Decibels, an image cropping and conversion tool called Switcheroo, and an ASCII-art generator called Letterpress, which is an amusing tool, and it does generate some impressive ASCII artwork. By default it generates images at a "resolution" of 100 characters, but can go up to 500 characters wide. Another new entry is Railway, an application that provides travel information for users who are fortunate enough to live in areas with decent train service. It is, sadly, an application that is of little use in Durham, North Carolina.

Aside from showcasing GNOME libraries and technologies, the Circle applications also move users in the direction of installing software from Flathub. GNOME's Software utility allows users to browse a curated list of software available on a Linux distribution. It is a front-end for PackageKit, and supports RPMs and Debian packages (depending, of course, on the underlying distribution) and Flatpaks.

All of the applications announced with GNOME 46 are only available in the Store application as Flatpaks, at least right now. Most of the older applications in GNOME Circle also seem to be available only as Flatpaks, though a handful of older applications like the Déjà Dup backup tool are still available as RPMs on Fedora.

Some applications advertise that they are only available as Flatpaks. Biblioteca, an offline viewer for GNOME's developer reference materials, warns that "Biblioteca is made possible by Flatpak. Only Flathub Biblioteca is supported." The same is true of the Workbench application for prototyping GTK and GNOME applications. The applications are open source (GPLv3) and nothing would prohibit a distribution from providing native packages, but it's interesting how emphatic the maintainers are about a Flatpak-only distribution model.

GNOME 46 includes a few other changes that seem designed to encourage Flatpak use over native distribution packages. The first is showing a verified badge, which indicates that the application on Flathub is published by the original developer or a "third party approved by the developer". The verification process requires developers to put a verification token on the responsible organization's web site or the source code hosting site (e.g., GitHub or GitLab) in a repository the developer owns, or the developer needs to be an administrator or owner of the organization or group that owns the repository.

For example, if a developer for Acme Corp wanted to verify an application they would need to place the token on the web at

    https://acme.com/.well-known/org.flathub.VerifiedApps.txt

The token is simply a unique string of characters like 00000000-aaaa-0000-aaaa-000000000000. An organization can include multiple verification tokens in the text file if it is responsible for more than one application.

The manual process would make it hard to get a verified badge on Flathub for malware that impersonates a well-known application from GNOME, KDE, Mozilla, Signal, and so on. It does not entirely block a would-be malware publisher from playing a long game and trying to sneak malware in under a unique application name, but Flathub does put up a few hurdles to that approach as well.

First, Flathub verification requires a one-time manual approval by one of the Flathub administrators when an application is first uploaded. Hubert Figuière, one of Flathub's administrators, said via chat that some applications are abandoned during the verification process and that requests are closed after a year of inactivity. Secondly, Flathub applications are usually (with some exceptions like Mozilla) not uploaded directly to Flathub. Source is submitted to Flathub with a manifest, and the application is built by Flathub. Users can build a Flatpak locally if they wish to verify that it matches the source code repository. In the case of proprietary applications, build logs are available via Flathub, but the binary source is not available.

Finally, Flathub's build validation checks for changes to an application's requested permissions or metadata. Flatpak applications are run in a sandbox that provides some isolation from other applications and restricts access to system resources. If an update changes the requested permissions, or tries to change the application's name, then it will be held for manual review and may be rejected.

A verified application will have a blue check mark on its page in the Software application in GNOME. By sticking to verified software, users should be less likely to install anything malicious on their system. GNOME 46 makes this even easier by adding an option to only display software from verified developers. The downside to this is that Software only displays applications available via Flathub—it doesn't even display software from Fedora's standard repositories as verified.

GNOME also nudges users toward placing more trust in Flatpaks in its Settings application. In the Apps settings page, users can manage their applications' sandbox permissions, such as whether an application can send notifications or receive and send system search results. When looking at settings for an application that is installed as an RPM, Settings shows a blue bar underneath the window title that says "App is not sandboxed", with a small info button to the side.

If the user clicks this to learn more, then Settings helpfully informs them that application settings cannot be enforced for applications that are not sandboxed. It does not tell the user what sandboxing is, however, or if it is something the user can enable. A significant number of GNOME users will probably intuit that this means that the application is not installed as a Flatpak, but many others are likely to be confused. A pointer to better documentation, and perhaps a recommendation for an equivalent Flatpak, would be an improvement here. Well, it would be an improvement if one considers Flatpak a better application-packaging method than RPMs or Debian packages.

Flatpak, as a format, has some interesting features and provides convenience. But one of its trade-offs is that an application does not go through the rigorous packaging process that an application must go through to be in a Linux distribution's repository. In short, many Linux users have come to trust that software in their favorite distribution's repository has been fully vetted. Removing the distribution vendor or project from that process may be more expedient, but it has a number of downsides in terms of actual verification and examination of software.

Libadwaita 1.5

Another change in GNOME 46 is the update to Libadwaita 1.5. Adwaita is GNOME's "design language", and Libadwaita is the GTK 4 library that implements GNOME's human interface guidelines (HIG). Libadwaita is the library developers want if they are trying to develop an application that looks and feels like part of GNOME.

The big change in 1.5 is adaptive dialogs, which are dialogs that are attached to an application's main window. When a user opens the preferences for their GNOME application that uses Libadwaita 1.5, that dialog won't be a separate window.

GNOME developer Alice Mikhaylenko wrote about the rationale for the change in detail, but the primary goal is to improve support for applications on mobile devices where a separate dialog box does not make sense. On the desktop, it is debatable whether this is an improvement or not. As implemented right now, the dialog doesn't show up when tabbing between windows or even on the thumbnail for a window. So if a user opens the preferences for Letterpress, switches to another window, it effectively disappears if the user is expecting to see it when switching applications. It would be interesting to see how it works on a GNOME mobile device, but there are few such systems readily available.

Getting closer

Users have been looking for Variable Refresh Rate (VRR) support from GNOME for some time, and the project accepted a freeze extension to get the work done in time to land in GNOME 46. In a nutshell, VRR allows a device to adjust its refresh rate to match the frame rate of the video source. This is a particularly interesting feature for gaming, since the frames per second can fluctuate wildly while playing.

VRR support has required a great deal of work and testing over the years, not just in GNOME but also in Wayland. The good news is that it is now available in GNOME 46. The bad news is that it is an experimental feature at present, which means that users should temper expectations when trying it out. VRR can be toggled on with a gsettings command to enable the option to turn on VRR in settings:

    $ gsettings set org.gnome.mutter experimental-features "['variable-refresh-rate']"

I say "should" because VRR is not available with any combination of hardware that I've tried, including a gaming monitor that supports AMD FreeSync. Now that the VRR support is more widely available, though, it gives me hope that things will work in the not-so-distant future.

Extensions

The Extensions application has been retooled in this release as well. It features an upgrade assistant that checks compatibility with recent versions of GNOME to see if installed extensions are compatible with a newer (or older) release. This is useful to run before upgrading, and a little depressing to run afterward. One of the downsides to a new GNOME release is finding, once again, that some (or many) extensions don't work with the new release yet. In this case, six of the ten extensions on my system were unsupported, though one (ddterm) had an update available. Dash to Dock, Tray Icons Reloaded, WinTile, gTile, and Background Logo were all listed as unsupported.

This is such a common problem that the project has a page in the Guide to JavaScript for GNOME. The page explains why extensions break or stop working, why GNOME resumed version validation with GNOME 40, and how developers can avoid breakage by sticking to approved APIs or writing an application instead of an extension.

It is not hard to understand why the project would prefer that users and developers stick to the straight and narrow path of approved ways to extend and work with the desktop. And yet, users and developers keep trying to adapt GNOME to their needs and continue to find it frustrating. For many users, GNOME is almost perfect for their needs, with one or two exceptions. Extensions are often the only way to close the gap between almost perfect and perfect; or, at least, as close to perfect as one might manage with a desktop. Perhaps one day, GNOME and extension developers will manage to meet in the middle so that users can run the latest GNOME release and enjoy their favorite extensions too.

Overall, GNOME 46 is a solid release with quite a few improvements, and it's likely to be a little bit nicer by the time it lands in stable Linux releases. The upcoming Fedora 40 and Ubuntu 24.04 releases will have GNOME 46 by default, and it is already in Arch Linux and openSUSE Tumbleweed repositories.