gistfile1.txt

require("sdk/preferences/service").set("javascript.options.strict", false);

var { ActionButton } = require('sdk/ui/button/action');
var { Toolbar } = require("sdk/ui/toolbar");
var { Frame } = require("sdk/ui/frame");

var button = ActionButton({
  id: "my-button",
  label: "my button",
  icon: {
    "16": "./firefox-16.png",
    "32": "./firefox-32.png"
  }
});

var frame = new Frame({
  url: "./frame.html"
});

var toolbar = Toolbar({
  title: "My toolbar",
  items: [frame, button]
});