A year ago this Friday, a lot of you stood in line to catch a sold-out opening-weekend screening of Marvel’s Avengers: Endgame. After standing in another line for concessions, you found your reclining movie seat, sat down and swung over your tray, put your popcorn and soda on it and reached down to your right to find the plastic buttons that make the seat recline. Your hand came back up to dig into that communal popcorn tub you shared with a date, your kids, or your friends. Up goes that hand, toward your face, and…