Stephanie Nogueras, in real life like her character Amaya DeSoto is in fact deaf. Her sign language communication throughout the film is genuine signing utilized by the actress in interaction.
The trailer was uploaded first in the real dark web by the director himself.
There are two different theatrical endings.
Was originally called Unfriended: Game Night. It was likely changed to avoid confusion with the Jason Bateman led comedy Game Night (2018).
There are three completely different endings. Two theatrical endings were screened randomly. A third ending is included in the Blu-ray release in addition to the theatrical ending scenes.