do subscriptions execute once for each subscriber?

[shawnjones253]

https://typegraphql.com/docs/subscriptions.html

does the implementation body of the subscription resolver get executed once for each subscriber? or does it execute once and then the results are fanned out to subscribers?

what if the subscribers create the subscription and ask for a field from a FieldResolver? ex:

const COMMENTS_SUBSCRIPTION = gql`
  subscription OnCommentAdded($postID: ID!) {
    commentAdded(postID: $postID) {
      id
      content
    }
  }
`;

what if content is a FieldResolver?