anchor.diff:  
     // - - - - - - - - - - - - - - - - - - - - - - - -
     const makeIndexHtml = () => {
  -    const index = param.nowIndex;
  -    const colour = param.events[index].colour;
  +    const index = review.params.nowIndex;
  +    const colour = review.params.events[index].colour;
       const number = $(`.diff-traffic-light[data-index=${index}]`).data('number');
       return `<div id="index-number" class="${colour}">${number}</div>`;
     };
  
positive.code: 
    // - - - - - - - - - - - - - - - - - - - - - - - -
  
    setupButton('fork', () => cd.forkDialog(param.id, param.nowIndex));
    setForkButtonTip();
    if (!inTestPage) {
      $reviewPage.show();
  
negative.code: 
    // - - - - - - - - - - - - - - - - - - - - - - - -
    const moveToAvatar = (id) => {
      review.params.id = id;
      const index = review.inDiffMode() ? 1 : -1;
      review.moveToTrafficLight(index);
    };
  