I had the same thing happen to me the other day! I was fixing the dop targets on Pinbot and had propped the glass up against another cabinet, when my attention starved cat decided it would be cool to rub his face on everything in the basement...including the piece of glass. My back was turned as I was hunched under the playfield but I heard the loudest CRASH! I turned to see my cat tear-assing out of the basement and the piece of glass on the concrete floor...perfectly fine. Whoa!