Cheat in Chrome's "No network connection" dinosaur game. Paste this in the console when you find yourself on the screen (or disconnect from the internet and attempt to load a page).

dinosauras.js

const update_ = Runner.instance_.update;
Runner.instance_.update = function() { 
  if(this.horizon.obstacles.length) {
    const nearestObstacle = this.horizon.obstacles[0];
    if(nearestObstacle.xPos < 115 && !this.tRex.jumping) {
      if(nearestObstacle.yPos <= 50) {
        this.tRex.setDuck(true);
        setTimeout(this.tRex.setDuck.bind(this.tRex, false), 500);
      } else {
        this.tRex.startJump(this.currentSpeed);
      }
    }
  }

  update_.call(this); 
};