The specialization of full_message() in Koha::Exception::Object doesn't cover all possibilities – with no message passed in, and for all types except for the enumerated ones, the message ends up empty, never falling back to the parent's full_message. Patch incoming.
Created attachment 191928 [details] [review] Bug 41694: Ensure Koha::Exception::Object's full_message() always produces one Patch from commit e1c8f79