<script>
 function injectAllItem() {
  const ul = document.querySelector('.nested-category-tree-wrapper ul');
  if (!ul || ul.dataset.done) return;
  ul.dataset.done = '1';

  const li = document.createElement('li');
  li.className = 'category-item';
  li.innerHTML = '<a href="/shop" class="category-link root">All</a>';
  ul.insertBefore(li, ul.firstElementChild);
}

document.addEventListener('DOMContentLoaded', injectAllItem);
document.addEventListener('mercury:load', injectAllItem);
</script>