Option to have the app as a flatpak

It would be great if the app was packaged as a flatpak and made available through flathub.

In Ubuntu, it seems flatpaks work better than snaps with gnome, hence it would be great to have it as an install option.

Thanks!

There are around 200 daily downloads on flathub: Mailspring | Flathub. It would be great if flatpak was officially supported so that some issues could be reported and fixed upstream.