Add error checking to $tw.utils.setStyle()

core/modules/utils/dom/browser.js

@@ -18,11 +18,13 @@ Set style properties of an element
 	styles: ordered array of {name: value} pairs
 */
 exports.setStyle = function(element,styles) {
+	if(element.nodeType === Element.ELEMENT_NODE) {
 		for(var t=0; t<styles.length; t++) {
 			for(var styleName in styles[t]) {
 				element.style[$tw.utils.convertStyleNameToPropertyName(styleName)] = styles[t][styleName];
 			}
 		}
+	}
 };
 
 /*