Generalized Flatpak installation package

Pre-submission Checks

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Feature description

The ownCloud Client is currently available as a “linux-generic” AppImage. flatpak (see https://flatpak.org/) is another cross-distribution package format which has a growing number of users in many distributions (see Flatpak—the future of application distribution). There are GUI clients (like “Discover” on openSUSE) which make the installation extremely simple even for people who are not willing or are not able to use shell commands ("normal users").

I would recommend that the desktop client is also packaged for flatpak and available on dl.flatpak.org. by the way: the Nextcloud client is already available as a flatpak package

Proposed solution

desktop client as flatpak image

Alternative solutions you considered

none

Additional context

could replace AppImage in the middle run

Start by reviewing how the existing linux-generic AppImage is packaged for the desktop client, then compare the requested Flatpak distribution path with the existing Nextcloud client package. Done means the ownCloud desktop client is packaged as a Flatpak image and made available through the proposed distribution channel; no specific files or tests are named in the issue.