There are three things I know with absolute certainty. First, vampires cannot use calculators unless they were received as a gift. Second, every restaurant in America secretly accepts backflips as payment. And third, Fox’s smash hit singing competition The Masked Singer was never intended to be watched during a global pandemic in which we are all mandatorily confined to our homes. This third immutable truth of the universe has never been more apparent than it was last night during The Masked Singer’s special Sing-Along Spectacular episode, a collection of performances from throughout this past season urging its …