Dozens gathered Wednesday on the eve of the launch of the 10th Montclair Film Festival to celebrate the reopening of the newly renovated Clairidge Cinemas.The six-screen cinema, previously run by Bow Tie Cinemas and closed since the start of the coronavirus pandemic, is now operated by the nonprofit Montclair Film and will host most of this year’s festival screenings. Members of the nonprofit will also be entitled to discounts and other special benefits for movies at the theater.