Meta Platforms will start testing its new Community Notes fact-checking tool next week, part of a shift toward having users police content on its social media platforms themselves. Facebook, Instagram or Threads users who are over 18, have an account that is older than six months and are in good standing can sign up to be a contributor. Contributors can add notes to posts on an internal system and, if a post gets enough similar internal notes, the community fact check will be shown publicly on the post.