How to HTTP POST a Flux<String> as a JSON array using Spring's WebClient?

How do I use Spring's reactive WebClient to POST a Flux<String> as a JSON array?

Flux<String> stringFlux = Flux.fromIterable(objects).map(MyObject::getSomeString);

WebClient.create(baseUrl)
  .post()
  .uri(myUrl)
  .contentType(MediaType.APPLICATION_JSON)
  .body(stringFlux, String.class)
  .exchange()
  .flatMap(response -> {
     if (response.statusCode().is2xxSuccessful()) {
       // Do something
     }
     return response.bodyToMono(Void.class);
   })
   .block();

This sends the request, but it's not sending it as a JSON array of strings.

I saw that there's another body() signature that accepts a ParameterizedTypeReference, so I tried this:

.body(stringFlux.collectList(), new ParameterizedTypeReference<>() {})

but this results in a compile error actually (I'm on Java 11):

Error:java: com.sun.tools.javac.code.Types$FunctionDescriptorLookupError.

Any ideas?