Hi! The new appstream upload is available, which fixes the issue affecting Lintian. Maybe lintian should only read from appstreamcli's stdout for YAML parsing and ignore stderr, that way GLib warnings wouldn't trip it up. Anyway, the Lintian thing unfortunately wasn't this bug, so, I still have no idea how to reproduce it. So far, no bug reporter has come back with further information...
Cheers,
Matthias
