https://www.humanbenchmark.com/tests/reactiontime/

crackGame.js

const ele = document.querySelector('body > div.hero > div > div.test-wrapper.ng-scope > div');
  let flag = true;
  const mouseDownEvent = document.createEvent('MouseEvents');
  mouseDownEvent.initEvent('mousedown', true, true);
  const observer = new MutationObserver((mutations) => {
    mutations.every((mutation) => {
      if(mutation.target.classList.contains('view-go') && flag){
        ele.dispatchEvent(mouseDownEvent);
        flag = false;
        return false;
      }
      return true;
    });
  });
  const config = { attributes: true, attributeFilter: ['class'] };
  observer.observe(ele, config);