NFL overtime playoff rules were changed. Here's how they work now.
NFL overtime rules could be changed at owners' meetings - Los Angeles Times
NFL changes overtime rules: Now both teams get a possession in playoffs
NFL owners approve rule change for OT in playoffs
NFL approves overtime rule change for playoffs only - Niners Nation
NFL changes playoff overtime rule after Kansas City Chiefs vs Buffalo Bills thriller, National Sports
Bills Notebook: NFL's overtime rules fall under the spotlight after classic playoff game
NFL changes overtime format only for playoff games - The Washington Post
NFL overtime rules for playoffs, explained: How is winner determined?
NFL owners change overtime playoff rule