Note: After saving, you have to bypass your browser's cache to see the changes. Google Chrome, Firefox, Microsoft Edge and Safari: Hold down the ⇧ Shift key and click the Reload toolbar button. For details and instructions about other browsers, see Wikipedia:Bypass your cache.
/**
 * Useful stuff from [[Wikipedia:WikiProject_User_scripts]]
 */

function addToolboxLink(url, name, id){
  var tb = document.getElementById('p-tb').getElementsByTagName('ul')[0];
  addlilink(tb, url, name, id);
}

function addlilink(tabs, url, name, id, title, key){
  var na = document.createElement('a');
  na.href = url;
  na.appendChild(document.createTextNode(name));
  var li = document.createElement('li');
  if(id) li.id = id;
  li.appendChild(na);
  tabs.appendChild(li);
  if(id) {
    if(key && title) ta[id] = [key, title];
    else if(key)     ta[id] = [key, ''];
    else if(title)   ta[id] = ['', title];
  }
  // re-render the title and accesskeys from existing code in wikibits.js
  akeytt();
  return li;
}

function addTab(url, name, id, title, key){
    var tabs = document.getElementById('p-cactions').getElementsByTagName('ul')[0];
    addlilink(tabs, url, name, id, title, key);
}

function addPurge(){
    ta['ca-purge'] = ['g', 'Purge the internal cache for this page'];
    var x = document.getElementById('ca-history');
    if(!x) return;
    if(x.children) x = x.children[0].href;
    else x = x.childNodes[0].href;
    addTab(x.replace(/=history/, "=purge"), 'purge', 'ca-purge');
    akeytt();
}