title: FCM Topics Rate-Limit
body: <p>If you head over to Firebase's <a href="https://firebase.google.com/docs/cloud-messaging/ios/topic-messaging" rel="nofollow noreferrer">documentation</a> for Topics, it mentions there's a rate-limit for new subscriptions.</p>
  
  <blockquote>
    <p>The frequency of new subscriptions is rate-limited per project. If you
    send too many subscription requests in a short period of time, FCM
    servers will respond with a 429 RESOURCE_EXHAUSTED ("quota exceeded")
    response. Retry with exponential backoff.</p>
  </blockquote>
  
  <p>Does anyone know or tested how many requests per minute/second you can make?</p>