Someone

(addon-sdk-1.0b5)john@john-desktop:/e/scripts/xul/testing$ cat lib/main.js var contextMenu = require("context-menu");var request = require("request");var selection = require("selection");pageMod = require("page-mod").PageMod({  include: ["*.org"],  contentScriptWhen: 'start',  contentScript: 'window.stop();window.document.body.write("I like cheese");'});exports.main = function(options, callbacks) {  console.log(options.loadReason);   var menuItem = contextMenu.Item({     label: "Translate Selection",    context: contextMenu.SelectionContext(),    contentScript: 'self.on("click", function () {' +                   '  var text = window.getSelection().toString();' +                   '  self.postMessage(text);' +                   '});',    onMessage: function (text) {      if (text.length == 0) {        throw ("Text to translate must not be empty");      }      console.log("input: " + text)      var req = request.Request({        url: "http://ajax.googleapis.com/ajax/services/language/translate",        content: {          v: "1.0",          q: text,          langpair: "|en"        },        onComplete: function (response) {          translated = response.json.responseData.translatedText;          console.log("output: " + translated)          selection.text = translated;        }      });      req.get();    }  });}; exports.onUnload = function (reason) {  console.log(reason);};(addon-sdk-1.0b5)john@john-desktop:/e/scripts/xul/testing$ cfx runUsing binary at '/usr/bin/firefox'.Using profile at '/tmp/tmpq7ByJQ.mozrunner'.info: startuperror: An exception occurred.Traceback (most recent call last):  File "javascript:window.stop();window.document.body.write("I like cheese");", line 1, in TypeError: window.document.body is null