How to Install Flatpak on Debian Buster 10 Easy Guide

Installing

2. 2. Installing Flatpak

   Then to Install Flatpak
   First, is Strongly Recommended to Setup Backports Repo

   Backports Debian Buster/Stretch Setup Guide

   GNU/Linux Debian Buster/Stretch Backports Installation Guide

   Possibly, follow the instructions to Enable the ‘contrib‘ and ‘non-free‘ Sources.
   Then simply play:

   sudo apt install flatpak

   Authenticate with the User Admin Pass.
   If Got “User is Not in Sudoers file” then see: How to Enable sudo.
   Again for the GNOME Desktop integration run:

   sudo apt install gnome-software-plugin-flatpak

   And with this latest setup on GNOME based you’ll be able to Install Flatpak Apps just Double-clicking on the downloaded flatpakref File.