install flatpak: https://flathub.org/repo/flathub.flatpakrepo
System-wide applications = /var/lib/flatpak/app/
per-user applications = $HOME/.local/share/flatpak/app/
install flatpak: https://flathub.org/repo/flathub.flatpakrepo
System-wide applications = /var/lib/flatpak/app/
per-user applications = $HOME/.local/share/flatpak/app/