https://wccftech.com/developer-runs-flappy-bird-game-in-macos-interactive-notifications/

Apple removed the Flappy Bird game from the App Store back in 2014. While the game has not made an official comeback, a developer has recreated it in a way that we would never have imagined. A developer reincarnated the Flappy Bird game in macOS Big Sur push notifications. The best part of all is that you can play the entire game in interactive notifications.

Neil Sardesai, the developer, and designer behind the art made use of the UserNotificationsUI framework in macOS Big Sur. He was able to put a clone of the Flappy Bird game created by PlayCanvas creator Will Eastcott into macOS Big Sur's notifications. The creator showcased the game on Twitter where Sardesai utilized the interactive elements into macOS Big Sur's notifications. The mouse clicks represent the taps in the game which allows you to advance forward.