Bookmarklet to flip-flop GitHub's `relative-time` tag to use `format="datetime"`

flip-flop-relative-time.js

javascript:(()=>{
  const relativeTimes = document.querySelectorAll('relative-time[format="relative"], relative-time:not([format])');
  if (relativeTimes.length > 0) {
    for (let elem of relativeTimes) {
      elem.setAttribute('data-old-config', JSON.stringify({
        format: elem.getAttribute('format'),
        hour: elem.getAttribute('hour'),
        minute: elem.getAttribute('minute')
      }));
      elem.setAttribute('format', 'datetime');
      elem.setAttribute('hour', '2-digit');
      elem.setAttribute('minute', '2-digit');
    }
    console.log('Done setting attributes on ' + relativeTimes.length + ' relative-time tag(s).');
  } else {
    const oldRelativeTimes = document.querySelectorAll('relative-time[data-old-config]');
    if (oldRelativeTimes.length > 0) {
      for (let elem of oldRelativeTimes) {
        const oldConfig = JSON.parse(elem.getAttribute('data-old-config'));
        for (let attr in oldConfig) {
          const value = oldConfig[attr];
          if (value != null) {
            elem.setAttribute(attr, value)
          } else {
            elem.removeAttribute(attr)
          }
        }
        elem.removeAttribute('data-old-config');
      }
      console.log('Restored attributes on ' + oldRelativeTimes.length + ' relative-time tag(s).');
    } else {
      console.log('No relative-time tags found on this page.');
    }
  }
})();