Test Facebook Authentication from jsfiddle

I get this error message when i run try to authenticate facebook app from jsfiddle

Given URL is not allowed by the Application configuration.: One or more of the given URLs is not allowed by the App's settings. It must match the Website URL or Canvas URL, or the domain must be a subdomain of one of the App's domains.

http://jsfiddle.net/MyNameIsSakthi/K5hwY/1/

while(1){
   print("Thanks for answering!");
}

what must be the settings to be changes in Facebook App ?