diff --git a/src/iiiftilesource.js b/src/iiiftilesource.js
index d6635bf0..1c67bdc1 100644
--- a/src/iiiftilesource.js
+++ b/src/iiiftilesource.js
@@ -444,11 +444,10 @@ $.extend( $.IIIFTileSource.prototype, $.TileSource.prototype, /** @lends OpenSea
     /**
      * Determine whether arbitrary tile requests can be made against a service with the given profile
      * @function
-     * @param {array} options - IIIF profile array
-     * @param {Array|String} options.profile
+     * @param {Object} options - IIIF option
+     * @param {String} options.profile
      * @param {Number} options.version
      * @param {Number} options.extraFeatures
-     * @throws {Error}
      * @returns {Boolean}
      */
     function canBeTiled ( options ) {
diff --git a/src/viewer.js b/src/viewer.js
index 2f0f6f12..ca5b6303 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -1255,10 +1255,10 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
     //
     /**
      * @function
-     * @return {Boolean} returns true if the viewer is in fullscreen
+     * @returns {Boolean} returns true if the viewer is in fullscreen
      */
      isFullScreen: function () {
-        return $.setFullScreen.fullScreen;
+        return $.isFullScreen() && this.isFullPage();
     },
 
     /**