Steps to reproduce:
1. Create a scheduled event.
2. Delete the scheduler snapshot's properties for the event, using something like "DELETE FROM mh_assets_properties WHERE namespace = 'org.opencastproject.scheduler' AND mediapackage_id = 'foo-bar-baz-qux';
3. Try to delete the event.
The UI implies successful deletion. However, the event remains in the event list, ready to be deleted again.
The event should be deleted.
Workaround (if any):
There's no real workaround, though you could delete the event from the database manually.
Note that, as of now, we weren't able to consistently reproduce the problem, aside from manually altering the database. However, we do have production cases where events are not deletable because of missing properties.