[knot-dns-users] Zone breaks after update to 2.8.0

Hi @all I was trying to migrate knot to a new server with Ubuntu 18.04 and knot 2.8.0. I managed this by just copying the content of /var/lib/knot/* from the old to the new server. One of my domains threw an error when starting knot: knotd[5186]: error: [<zone>] zone event 'load' failed (malformed data) keymgr throws the same error. I dumped the data out of the 2.7.6 installation with mdb_dump and imported it into the 2.8.0 installation, which did not help. I then uninstalled 2.8.0 on the new server and installed 2.7.6, migrated data from the old server with the same procedure and it worked, no errors. Just out of curiosity I upgraded then the new server from 2.7.6 to 2.8.0 to see what will happen: It was the exact same behaviour, the zone couldn't load. How can I proceed here? There is obviously something wrong that the update breaks the loading of the zone. Is this on my end or a bug in knot? Thanks Simon