The App Requirements · flathub/flathub Wiki · GitHub page says
Flathub only hosts stable application releases, and not development snapshots. Manifests should therefore refer to tarballs or git tags and not the tip of a branch.
Both Resonance and Loupe are not stable yet. But they are available on Flathub. Resonance doesn’t even have any git tags.
So, has that policy changed but not yet reflected in the wiki or am I missing something?