component {8122e660-1012-11e2-892e-0800200c9a66} components/ndn-protocol-service.js
contract @mozilla.org/network/protocol;1?name=ndn {8122e660-1012-11e2-892e-0800200c9a66}
content modules modules/
content toolbar content/
overlay chrome://browser/content/browser.xul chrome://toolbar/content/toolbar.xul