Question

Here is the error that I am getting in Google Chrome:

Uncaught TypeError: Object #<HTMLDivElement> has no method 'webkitCancelFullScreen'

I get a similar error in Firefox.

Here is the code:

document.id('close-full-screen').addEvent('click', function() {
    document.id('full-screen').webkitCancelFullScreen();
});

Answer 1

According to the Documentation found here, webkitCancelFullScreen is called from the document object not a div. Thus, your code should be.

document.id('close-full-screen').addEvent('click', function() {
  document.webkitCancelFullScreen();
});

Here is an example using JSFiddle. The correct code can be found here.