In the Game of Thrones Episode leak, a YouTuber showed that Jon Snow and Daenerys will fight the army of the dead and the Night King together.
Game of Thrones Episode Leak: What Happened Between Jon Snow and Daenerys Targaryen?
In a clip released by a YouTuber (which can be taken down due to copyright claims) Jon Snow takes Daenerys in a cave beneath Dragonstone. Daenerys sees the Dragonglass but that is not the only thing she sees. Jon Snow shows her some marks of the Children of Forest and the First Men. The Children of the Forest and the First Men were at Dragonstone together to fight the White Walkers and the army of the dead. Daenerys agrees to fight the dead only if he will bend the knee.