old_contents: document.getElementById("ayuda").setAttribute("aria-current", "page");
  
  var aside = document.getElementById("complementario");
  var button = document.createElement("BUTTON");
  var text = document.createTextNode("Información sobre placeMarkers");
  button.appendChild(text);
  aside.appendChild(button);
  var div = document.createElement("DIV");
  
  function showAddonInfo(addon) {
  		var xhttp = new XMLHttpRequest();
  	xhttp.onreadystatechange = function() {
  		if (this.readyState == 4 && this.status == 200) {
  			var div.createElement("DIV");
  			var json = JSON.parse(xhttp.responseText);
  			div.innerHTML = json.name;
  		}
  	};
  	xhttp.open("GET", "https://api.github.com/repos/nvdaes/" + addon + "/releases/latest", true);
  	xhttp.send();
  }
  
  function showPlaceMarkersInfo() {
  	showAddonInfo("placeMarkers");
  }
  
  button.addEventListener("click", showPlaceMarkersInfo, true);
  
new_contents: document.getElementById("ayuda").setAttribute("aria-current", "page");
  
  var aside = document.getElementById("complementario");
  var button = document.createElement("BUTTON");
  var text = document.createTextNode("Información sobre placeMarkers");
  button.appendChild(text);
  aside.appendChild(button);
  
  function showAddonInfo(addon) {
  		var xhttp = new XMLHttpRequest();
  	xhttp.onreadystatechange = function() {
  		if (this.readyState == 4 && this.status == 200) {
  			var div = document.createElement("DIV");
  			var json = JSON.parse(xhttp.responseText);
  			div.innerHTML = json.name;
  		}
  	};
  	xhttp.open("GET", "https://api.github.com/repos/nvdaes/" + addon + "/releases/latest", true);
  	xhttp.send();
  }
  
  function showPlaceMarkersInfo() {
  	showAddonInfo("placeMarkers");
  }
  
  button.addEventListener("click", showPlaceMarkersInfo, true);
  
subject: Fix script