Traditionally, apps on Flathub have mostly been Gtk apps that integrate well into the Gnome desktop. However, recently elementary OS has announced that it will transition to using Flatpaks as the primary source of distributing applications, which is why more and more elementary OS apps have been uploaded to Flathub. elementary OS has a different design language than Gnome, but since elementary apps also use Gtk (applying a stylesheet and expanded with Granite), when users of Gnome install an app, they may be surprised that it looks different than the screenshot (Gnome uses a different stylesheet), or some functions donât work out of the box, or the app doesnât work at all, because the app has been design for elementary OS.
Now, whenever I use Gnome Software to browse for apps, I see Gnome applications mixed with elementary OS ones. With more and more platforms supporting and showing Flathub apps in their software store, I propose that Flathub introduce a âtarget platformâ functionality that allows developers to specify on which platforms their apps are optimized and built for. Then, we can reach upstream to Gnome and the others so that they can hide or display a warning message in their software store for apps that donât integrate well.
We can also do the same thing for X11/ Wayland. If the app doesnât support Wayland, or some functions donât work, the users should know before installing it too.
Case in point: this app, Ciano, is designed for elementary OS. However, users on Gnome Software can see it and install it too because it is a Flatpak. Now the review has multiple people criticizing it because it doesnât follow Gnome design guidelines and doesnât work on Gnome. This isnât fair to the developers at all.
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I wouldnât say that Flathub has âtraditionally had mostly GNOME GTK appsâ. Thereâs been a longstanding presence from the KDE community and other communities, many of whose apps are considerably more popular! However I do understand your user need. I think that this isnât really something where flathub on its own would look to help out, however Iâd see this sort of filtering being best expressed in appstream metadata within the app and then used by your software store of choice (GNOME Software, Pacmac, KDE Discover etc.) to help curate. Certainly people have used various bits of appstream to do that. Thereâs also some fields in some desktop files that can be parsed and exposed.