How to enable Flatpak in Kubuntu 23.10

[Schwarzer Kater]

If you want to use Flatpaks complementary to or instead of Snaps you will have to manually enable Flatpak support in Kubuntu 23.10 first:

Here is a step-by-step tutorial:

1. open the Konsole terminal emulator from the -> Application Launcher -> System
2. enter
   sudo apt update && sudo apt install flatpak plasma-discover-backend-flatpak kde-config-flatpak and your password
   (this will install three things:
   a) the system's Flatpak support itself (which can be used in CLI, see flatpak --help and man flatpak),
   b) the Discover support for Flatpak to find, install, update and remove Flatpaks with the Discover software center and
   c) the Flatpak Permissions Settings module for System Settings to manage their permissions in -> Application Launcher -> Settings -> System Settings -> Applications)
3. to enable the Flathub repository for Flatpaks
   EITHER in Konsole enter
   flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
   OR in the -> Application Launcher -> System -> Discover software center
   -> in the left part go to Settings -> click the button at the right side [Add Flathub]
   (both will enable the Flathub repository for Flatpaks, which is currently the largest one and is supported by e.g. KDE and GNOME - you can enable other Flatpak repositories like e.g. the one from Fedora or from individual developers later on if you wish to do so)
4. restart your system or at least log out and in again
5. done - you can now use Flatpaks and manage them with Discover and their permissions with System Settings (or you can do all of that in Konsole of course)

Please know that both Flatpaks and Snaps use up more space of your storage medium than programs "traditionally" installed by apt.
Flatpaks have some advantages and disadvantages that Snaps don't have and vice versa.


PS:
There is a (purely graphical) method that might be easier for some people as claydoh pointed out in the next post.

Be aware that the purely graphical method does not install the Flatpak Permissions Settings module for System Settings - you will still have to install this in Konsole with sudo apt install kde-config-flatpak.

[claydoh]

The easier method, for some folks:


Reboot, as prompted


This may or may not be available in 22.04, I don't have a 'clean' setup to check atm. I *thought* it works the same, but cannot confirm.

[Schwarzer Kater]

Thank you very much for your addition!

[Schwarzer Kater]

[…]
This may or may not be available in 22.04, I don't have a 'clean' setup to check atm. I *thought* it works the same, but cannot confirm.

I just tested it in a "vanilla" Kubuntu 22.04 LTS - unfortunately the "Install Missing Backends" option is not availabe there in Discover's settings.
I also tested it in a "vanilla" Kubuntu 23.04 - there it does work!

So this "easier method" only works in Kubuntu 23.x. - I also linked your post from the Kubuntu 23.04 tutorial.