docs: private Response followPostRedirect(Response response) throws IOException {
      String location = response.header("Location");
      if (location == null) {
        throw new IllegalStateException(format("Missing HTTP header 'Location' in redirect of %s", response.request().url()));
      }
      HttpUrl url = response.request().url().resolve(location);
  
      // Don't follow redirects to unsupported protocols.
      if (url == null) {
        throw new IllegalStateException(format("Unsupported protocol in redirect of %s to %s", response.request().url(), location));
      }
  
      Request.Builder redirectRequest = response.request().newBuilder();
      redirectRequest.post(response.request().body());
      response.body().close();
      return okHttpClient.newCall(redirectRequest.url(url).build()).execute();
    }