Open external links in a new tab/window

targetBlank.js

window.onload = function() {
  var anchors = document.getElementsByTagName('a');
  var a = new RegExp('/' + window.location.host + '/');
  for (var i = 0; i < anchors.length; i++) {
    if (!a.test(anchors[i])) {
      anchors[i].setAttribute('target', '_blank');
    }
  }
};