Polyfill element.closest() for older Firefox OS

Author: ferndot

index.html

@@ -34,6 +34,7 @@
 	<script type="text/javascript" src="scripts/lib/jszip-load.js" defer></script>
 	<script type="text/javascript" src="scripts/lib/codemirror-compressed.js" defer></script>
 	<script type="text/javascript" src="scripts/lib/fxosrate.js" defer></script>
+	<script type="text/javascript" src="scripts/lib/closest.js" defer></script>
 
 	<!-- Localization -->
 	<meta name="defaultLanguage" content="en">

scripts/lib/closest.js

@@ -0,0 +1,17 @@
+(function (ELEMENT) {
+	ELEMENT.matches = ELEMENT.matches || ELEMENT.mozMatchesSelector || ELEMENT.msMatchesSelector || ELEMENT.oMatchesSelector || ELEMENT.webkitMatchesSelector;
+
+	ELEMENT.closest = ELEMENT.closest || function closest(selector) {
+		var element = this;
+
+		while (element) {
+			if (element.matches(selector)) {
+				break;
+			}
+
+			element = element.parentElement;
+		}
+
+		return element;
+	};
+}(Element.prototype));