I run Debian 13 Stable with KDE Plasma, and have Flathub enabled on KDE’s Discover software store. I have a slight idea of the difference between the two: that Debian packages share system libraries and are therefore lighter in storage but do require password to access those shared libraries and could therefore become a security hazard if installing from an untrusted source, while Flatpaks have all they need and don’t require password to install, being more secure that way, but, as a consequence, consume more storage. Also noticeable is the fact that, for some programmes, the Flatpak version tends to be more recent and it therefore becomes the obvious choice when looking for the latest software.
However, I was looking at the SuperTux game, and what’s curious about this is that both, the Debian package and the Flatpak are version 0.6.3, while consuming 6.7 and 259,9 MB of storage respectively.
So should the obvious choice here be the Debian package, or would you still go for the Flatpak? I am not asking this because I’m particularly interested on this game as much as to learn more about the two system packages and whether my assumptions are correct or I am missing something.
Thank you and have a nice weekend!


I’d say if the version is the same, go with the Debian packages and then fall back to the Flatpak one if it doesn’t work.
The 260MB of storage for Flatpak is a bit misleading though. If you have other flatpaks installed, it’s smart enough to deduplicate the files and share them.
Another thing to consider is xdg compliance. If you’re really picky about having a nice clean home directory and the program likes to vomit files into it, Flatpak keeps that contained in its sandbox. Not something to worry about for most people though.