reactor-core/src/main/java/reactor/core/publisher/Flux.java
public final Mono<Void> thenEmpty(Publisher<Void> other) {
		return then(Mono.fromDirect(other));
	}
public final Mono<Void> thenEmpty(Publisher<Void> other) {
		return then(Mono.fromDirect(other));
	}
Return a {@code Mono<Void>} that waits for this {@link Flux} to complete then
for a supplied {@link Publisher Publisher&lt;Void&gt;} to also complete. The
second completion signal is replayed, or any error signal that occurs instead.
<p>
<img class="marble" src="doc-files/marbles/thenEmptyForFlux.svg" alt="">

@reactor.discard This operator discards elements from the source.

@param other a {@link Publisher} to wait for after this Flux's termination
@return a new {@link Mono} completing when both publishers have completed in
sequence