diff --git a/static/js/script.js b/static/js/script.js
index f990811..890781e 100644
--- a/static/js/script.js
+++ b/static/js/script.js
@@ -217,3 +217,8 @@ function convertHtml(str) {
 
 String.prototype.startsWith = function(str)
 {return (this.match("^"+str)==str)}
+
+String.prototype.endsWith = function(suffix) {
+	if (this.length < suffix.length) return false;
+	return this.lastIndexOf(suffix) === this.length - suffix.length;
+}