filter Elements instead of HTMLElements

lib/single-file/doc-helper.js

@@ -132,7 +132,7 @@ this.docHelper = this.docHelper || (() => {
 	}
 
 	function getElementsInfo(win, element, elementsInfo = new Map()) {
-		const elements = Array.from(element.childNodes).filter(node => !win || node instanceof win.HTMLElement);
+		const elements = Array.from(element.childNodes).filter(node => !win || node instanceof win.Element);
 		elements.forEach(element => {
 			getElementsInfo(win, element, elementsInfo);
 			const computedStyle = win.getComputedStyle(element);