[zozbot234]

No real need for full Flatpak, Bubblewrap (bwrap) is intended to be a lightweight sandbox providing this out of the box, with Flatpak (and other stuff besides) building upon it. The Arch wiki has a nice introductory page: https://wiki.archlinux.org/title/Bubblewrap

[moody5bundle]

Oh didn't know about bwrap yet! If i understand the wiki page correctly, you still need to get those binaries to your pc. So thats why i went with plain and simple dockerfiles.