This script creates functions that add aria-hidden="true" to all elements except for the element specified.

hideFromAT.js

// Hide and unhide from assistive technology (AT)


const hideFromAT = function(el){
    const { body } = document;
    let currentEl = el;

    // If there are any nodes with oldAriaHiddenVal set, we should
    // bail, since it has already been done.
    const hiddenEl = document.querySelector('[data-original-aria-hidden]');

    if (hiddenEl !== null) {
      // eslint-disable-next-line no-console
      console.warn('Attempted to run hideFromAT() twice in a row.  unhideFromAT() must be executed before it run again.');
      return;
    }

    do {
      // for every sibling of currentElement, we mark with
      // aria-hidden="true".
      const siblings = currentEl.parentNode.childNodes;
      for (let i = 0; i < siblings.length; i++) {
        const sibling = siblings[i];
        if (sibling !== currentEl && sibling.setAttribute) {
          sibling.setAttribute('data-original-aria-hidden', sibling.ariaHidden || 'null');
          sibling.setAttribute('aria-hidden', 'true');
        }
      }

      // we then set the currentEl to be the parent node
      // and repeat (unless the currentNode is the body tag).
      currentEl = currentEl.parentNode;
    } while (currentEl !== body);
  };

const unhideFromAT = function() {
    const elsToReset = document.querySelectorAll('[data-original-aria-hidden]');

    for (let i = 0; i < elsToReset.length; i++) {
      const el = elsToReset[i];
      const ariaHiddenVal = el.getAttribute('data-original-aria-hidden');
      if (ariaHiddenVal === 'null') {
        el.removeAttribute('aria-hidden');
      } else {
        el.setAttribute('aria-hidden', ariaHiddenVal);
      }
      el.removeAttribute('data-original-aria-hidden');
    }
  };