This works also, and doesn't require a hosted file: https://xss-game.appspot.com/level6/frame#data:text/plain,alert(1) https://xss-game.appspot.com/level6/frame

This works also, and doesn't require a hosted file: https://xss-game.appspot.com/level6/frame#data:text/plain,alert(1) https://xss-game.appspot.com/level6/frame#data:text/plain,al...