HBO Max Watch Party is a capable and free-to-use browser extension. By the virtue of the name you can assume that users can host and join watch parties for HBO Max using this add-on. All you need is an active HBO subscription and a secure web browser to use the extension successfully. Furthermore, you can binge-watch your HBO favorites in sync and in high definition. The extension works by synchronizing the video playback for every user so that everyone enjoys the same content simultaneously.