A mismatch between the appstream2 branch and delta indexes caused local Flatpak clients to fail to update appstream data. The issue is resolved now after regenerating both the branch and the indexes.

If you are still experiencing issues, please try the steps below to clear the local copy of the appstream2 branch. (01:33 UTC — Mar 25)

# For system-wide installation 
sudo ostree --repo=/var/lib/flatpak/repo refs --delete flathub:appstream2/x86_64

# For user installation
ostree --repo=$HOME/.local/share/flatpak/repo refs --delete flathub:appstream2/x86_64

# Update the appstream data
flatpak update --appstream

Additionally, some client experienced timeouts when fetching delta indexes that were removed from the server. This was caused by the CDN not caching 404 responses, resulting in requests queuing up behind nginx’s cache lock. A fix was deployed to cache 404 responses, allowing clients to gracefully fall back to full downloads. (02:08 UTC — Mar 25)