This repo contains the flatpak version of Nagstamon (https://github.com/HenriWahl/Nagstamon)
flatpak-builder --repo=local-repo --force-clean build-dir de.ifw_dresden.nagstamon.yml
flatpak --user remote-add --no-gpg-verify local-repo local-repo
flatpak --user install local-repo de.ifw_dresden.nagstamon
flatpak run de.ifw_dresden.nagstamon
flatpak uninstall --user de.ifw_dresden.nagstamon