https://techcrunch.com/2020/09/17/hulu-tests-its-co-viewing-feature-watch-party-with-ad-supported-viewers/

Hulu was one of the first major streaming services to introduce a “co-viewing” feature that allows friends and family to watch Hulu content together from different locations. The feature, Hulu Watch Party, was initially only available for subscribers on the the ad-free tier of Hulu’s streaming service. Now, the company is making Watch Party available to ad-supported subscribers as well, but in a more limited capacity.

When Hulu Watch Party launched in May, it worked across thousands of movies and TV shows in Hulu’s on-demand streaming library. As Hulu explained at the time, if a show is available for co-viewing, it will indicate this with a “Watch Party” icon on the title’s Details page. Users can then provide the co-viewing link to those they want to watch together with. Currently, a Watch Party session supports up to 8 people.