docs: function( xhr ) {
  		try {
  			// IE error sometimes returns 1223 when it should be 204 so treat it as success, see #1450
  			return !xhr.status && location.protocol == "file:" ||
  				( xhr.status >= 200 && xhr.status < 300 ) || xhr.status == 304 || xhr.status == 1223;
  		} catch(e){}
  		return false;
  	}