public struct Statistics: Equatable {
        public let tweetCount: Int
    }

    /// Return database infos
    public func statisticsPublisher() -> AnyPublisher<Statistics, Error> {
        ValueObservation.tracking { db in
			// If I uncomment this, the observer works.
            // _ = try Tweet.all().fetchAll(db)
            return Statistics(tweetCount: try Tweet.all().fetchCount(db))
        }
        //.removeDuplicates()
        .publisher(in: dbPool).eraseToAnyPublisher()
    }