Fancybox not loading certain sites given in href

I want to load certain website in fancybox. This is my code:

  $.fancybox({
                'width': '85%',
                '开发者_开发技巧height': '85%',
                'type': 'iframe',
                'href': 'https://twitter.com',
                'transitionIn': 'elastic',
                'transitionOut': 'elastic'
             });

As you can see I am loading twitter.com in href. The request is sent when I saw it in Fiddler but the page doesn't render. Any idea what can be wrong?

Note: I am already using latest version of fancybox i.e 1.3.4.

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Twitter.com uses frame breakers because of clickjacking attempts in the past. That is probably the reason why it is not working.

If you are trying to display your feed, use their api.