The Harry Potter play, based on a new story by author J.K. Rowling in collaboration with Jack Thorne and John Tiffany, announced Monday that it had set a Broadway record for the strongest preview grosses: $2.1 million in ticket sales for the week ending Sunday at the Lyric Theatre. The Potter news came on the same day that Disney Theatrical Productions announced that its stage musical adaptation of “Frozen” had broken a house record at the St. James Theatre for the second week in a row. After grossing $2,246,997 for the week ending April 1, “Frozen” went on to gross $2,275,395 the following week.