How to use Flatpak to manage sandboxed applications on Fedora Workstation 28

With the use of modern Gnu/Linux distributions package managers, package dependencies are no more a problem per-se, but usually each distribution ships with a certain version of a program, and we want to install a new version we have to compile it, or rely on third party repositories. The same thing happens if the repositories of our favorite distribution doesn’t contain a certain application we need. Also for an application distributor can be time-consuming having to provide different package formats for the same application.