Provide an AppData metadata file In order to be published by flatpak-friendly software distributions, I have to provide this kind of metadata. I have chosen to give it as an XSLT stylesheet to apply on a list of releases, because it may change independently of the source code (as the releases are purely git tags). I have also provided a mechanism to extract releases from the git tags automatically. The release messages are simply the git tags, converted from org-mode to HTML. This is interesting because the appstream metadata supports HTML to a certain extent. Finally, I have set up a strict validation with appstream-util. Unfortunately, the CI/CD pipeline runs on the old debian, so the launcher tag is not supported.