[Linux] Add application metainfo

[A6GibKm]

Most GNU/Linux desktop environments like GNOME and KDE follow the freedesktop specification, which requires a appname.metainfo.xml file at /usr/share/metainfo or $XDG_DATA_HOME/metainfo to provide metainfo about the app, which will be picked by the software store app or the environment in general. It is considered good practice to add a metainfo or appdata file for a package distribution.

• Appstream: Metadata Quickstart
• Freedesktop.org

I made a metainfo file at flathub/ch.protonmail.protonmail-bridge which can be used as a reference.

I am sure this has been brough up many times in the past, but I was not able to find a place to start a discussion with the community.

NOTE: This is not a Flatpak related issue. It just happens that Flatpak builds require a metainfo.

[horejsek]

Thank you for suggestion. I don't remember this request so I think this if brought up for the first time. ;-)

[zestygrass]

Hi, I read the related issue #72, last update on that was almost 3 years ago and the issue is closed so I'll ask this here. Many popular desktop email applications on Linux are now officially packaged as flatpak e.g. thunderbird, evolution, kontact.

Since this was last brought up has proton reconsidered supporting flatpak release/packaging?