From Hard Drop - Tetris Wiki
||This game is partially on Facebook.
You must register to sync your progress (13+ birth date required), but you do not need to register to play.
Note: This template is intended to supplement 13a or 13b for the leaderboard used in games that are partially on Facebook.
This template is only used when the game is partially on Facebook (like earning extra coins for your leaderboard), but you do not need to log in to Facebook to play normally.