We want to move to flatpaks as much as possible, and stop including apps like firefox as rpms in the OS image. Since we still want to preinstall a useful set of applications, we need to be able to preinstall flatpaks.
From a hallway discussion with Colin a while ago, this probably requires us to have a flatpak repository on the iso and install the apps from there.
I've started some initial discussion on this here:
Endless is working on p2p support for ostree and flatpak that will be useful for this.
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