Identical events not handled properly, not sure if intentional

If I publish one event multiple times then

UPDATE EVENT_PUBLICATION
			SET COMPLETION_DATE = ?
			WHERE
					LISTENER_ID = ?
					AND SERIALIZED_EVENT = ?

Will update completion date on all of the records in the database: ones already completed and ones not even processed yet.

Should there be a unique constraint on listener_id and serialized_event or probably a better way to find the current record to update?

Actually stumbled upon this one by getting deadlocks when sending a lot of identical events and was wondering how a simple create then update once can deadlock :)

EDIT: I understand that modulith tries to guarantee at least once delivery so it doesn't break that but I still have that feeling that this could be handled in a more transparent way, would failing to process an identical event be considered bad?

Start by tracing the EVENT_PUBLICATION update statement and reproduce the deadlock with repeated identical events. Determine how the current record is selected without updating completed or unprocessed records, while preserving at-least-once delivery. Done means the behavior is defined and the update no longer affects unrelated publication records.