document.addEventListener("DOMContentLoaded", function () {
  var aside = document.querySelector("aside.sidebar");
  var specials = document.querySelector(".actions-special");
  if (!aside || !aside.children.length || !specials) return;

  var item = document.createElement("button");
  item.type = "button";
  item.className = "btn btn-block";
  item.title = "Contents";
  item.textContent = "CONTENTS";
  item.addEventListener("click", function () {
    if (typeof openOverlay === "function") openOverlay(aside);
  });
  specials.appendChild(item);
});