I'm trying to use the Youtube Iframe API inside a module definded with Require JS. As this API is loaded async and calls a function once is loaded, I used a requireJS plugin called "async", that worked before with google maps api. However, this time something isn't working. My module starts this way: define(['text!fmwk/widgets/video/video.html','fmwk/utils/browser','async!http://www.youtube.com/iframe_api'], function (videoTpl,root) { ... }); and chrome console fires this error: Uncaught Error: Load timeout for modules: async!http://www.youtube.com/iframe_api_unnormalized3,async!http://www.youtube.com/iframe_api http://requirejs.org/docs/errors.html#timeout If I don't use async plugin the object YT or its functions are undefinded, and the same happens if I download the API code. The API is loaded sometimes if I put an script tag in the head tag of the html file. All this is expected, but I don't understand because async plugin fails. Thank you for your attention and help :)