Can't update a topic's body by API

Development
4

Wow, you are right, it works :sparkling_heart:

And I figured out how to retrieve the ID of the first post in a topic using the Discourse API:

async function getFirstPostIdFromOnetopic(topic_id) {
  const Discourse_API_Key = "Discourse_API_Key";
  const url = `https://discourse.mysite.com/t/${topic_id}/posts.json`;

  const response = await fetch(url, {
    method: 'GET',
    headers: {
      "Api-Key": Discourse_API_Key,
      "Api-Username": "system",
      "Content-Type": "application/json",
    }
  });
  const data = await response.json();
  const firstPostId = data.post_stream.posts[0].id;
  
  return firstPostId;
}

Thank you and @Lilly :innocent: