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.
 // [[User:Henrik/sandbox/google-search]] (please include this line)
 function install_search()
 {
var elem;
  if (skin == "vector") {
    elem = document.getElementById('searchform').parentNode;
  } else {
    elem = document.getElementById('searchBody');
  }
  elem.innerHTML +=
 '<FORM method=get action="http://www.google.com/search">'+
 '<input type=hidden name="ie" value="UTF-8" /><input type=hidden name="oe" value="UTF-8" />'+
 '<INPUT id="searchInput" name="q" type="text" accesskey="f" value="" />'+
 '<input type="hidden" name="domains" value="en.wikipedia.org" />'+
 '<input type=radio name=sitesearch value="">Web'+
 '<input type=radio name=sitesearch value="en.wikipedia.org" checked />WP'+
 '<INPUT type="submit" name="btnG" VALUE="Google Search"  /></FORM></div>';
 }
 addOnloadHook(install_search);