Florida Theatre President Numa Saisselin is inviting the public to a celebration of the venue’s 90th birthday at 7 p.m. Saturday. Admission is free and includes a screening of the silent film classic, “Steamboat Bill Jr.,” starring Buster Keaton. A live soundtrack will be conducted by Jacksonville University artist-in-residence and percussionist Tony Steve — the way films were shown on April 8, 1927, when the theater opened. Cupcakes will be served and the full-service bar in the lobby will be open. Former Mayor Jake Godbold, who was instrumental in the acquisition and restoration of the historic building in the 1980s, is scheduled to make an appearance. Although a sponsorship by The Haskell Co. is covering the cost of the event, “It’s not a fundraiser in disguise,” said Saisselin. “We’re saving that for our $250-a-ticket annual gala on May 20.”