Find the elements that are causing a horizontal scroll. Based on http://css-tricks.com/findingfixing-unintended-body-overflow/

debug-scroll.md

Debug Horizontal Scroll

(() => {
  let { offsetWidth, offsetHeight } = document.documentElement;
  let walker = document.createTreeWalker(document.body, NodeFilter.SHOW_ELEMENT);
  while (walker.nextNode()) {
    let bound = walker.currentNode.getBoundingClientRect();
    let isWidthOverflow = bound.right > offsetWidth || bound.left < 0;
    let isHeightOverflow = bound.bottom > offsetHeight || bound.top < 0;
    let { style } = walker.currentNode;
    if (isWidthOverflow && isHeightOverflow) {
      style.setProperty('outline', '1px dotted red', 'important');
    } else if (isWidthOverflow) {
      style.setProperty('outline', '1px dotted maroon', 'important');
    } else if (isHeightOverflow) {
      style.setProperty('outline', '1px dotted darkviolet', 'important');
    } else {
      continue;
    }
    console.log(walker.currentNode);
  }
})();

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