I honestly thought that Steam Boat Willie was the first use of synchronized sound before I looked this up. At this point I don't know why I am surprised.https://disney.fandom.com/wiki/Celebrity_Productionshttps://www.fleischerstudios.com/filmography.htmlhttps://cartoonresearch.com/index.php/max-and-dave-thats-the-way-the-ball-bounces-chapter-1/https://www.fleischerallstars.com/oh-mabel.html ...