I'm also missing this, I've installed the RPM version of Cider 3 for now and everything is working fine, but I'd prefer to go back to the Flatpak package if possible.
Would be great if a Flatpak repo was added as another download option alongside the distro-specific package repos. In the meantime, I put together a Flatpak manifest that can be used to convert the AppImage to a Flatpak.
The release published on Flathub that you're seeing through Bazaar is very old - I think it's the last open source release.
The AppImage will run on Bazzite, and you could probably also install one of the packages inside a distrobox and export it - Bazzite ships with distrobox installed. The manifest I put together and linked above is also an option and makes it pretty easy to convert your AppImage download to a .flatpak with a few commands - you only need to install flatpak-builder, which is available as a flatpak itself.
