Flatpak will no longer feature in the default install of Ubuntu's 8 official flavors, with devs agreeing to only support deb and snap software OOTB.

In a surprise move, Ubuntu developers have agreed to stop shipping Flatpak, preinstalled Flatpak apps, and any plugins needed to install Flatpak apps through a GUI software tool in the default package set across all eight of Ubuntu’s official flavors, as of the upcoming Ubuntu 23.04 release.