diff --git a/.gitignore b/.gitignore
index 31dc5a837fb..5324150c8f8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -51,3 +51,4 @@ nbproject/
 *.log
 samples/highcharts/common-js/browserify/demo.js
 samples/highcharts/common-js/webpack/demo.js
+/samples/cloud/charts
diff --git a/cloud-downloader.js b/cloud-downloader.js
index 1f6c73ab506..32740e3219f 100644
--- a/cloud-downloader.js
+++ b/cloud-downloader.js
@@ -1,20 +1,42 @@
-"use strict";
+/* eslint-env node, es6 */
+/* eslint no-console: 0, require-jsdoc: 0 */
+
+/**
+ * This script retrieves the n most popular charts from cloud.highcharts.com, downloads
+ * the configurations and prepare them for side-by-side testing in
+ * http://utils.highcharts.local/samples.
+ * The downloaded charts can be viewed under the "cloud" heading.
+ */
+
+'use strict';
 
 let co = require('co');
 let fs = require('co-fs-extra');
 let request = require('co-request');
 let properties = require('properties');
 
+
+function wrap(script) {
+    return 'window.addEventListener("DOMContentLoaded", function () {' + script + '});\n';
+}
+
+function html(hash) {
+    return '<script src="https://code.highcharts.com/stock/highstock.js"></script>' +
+        '<script src="https://code.highcharts.com/stock/modules/data.js"></script>' +
+        '<script src="https://code.highcharts.com/stock/modules/exporting.js"></script>' +
+        '<div id="highcharts-' + hash + '"></div>';
+}
+
 co(function* () {
     let props = yield new Promise((resolve, reject) => {
-        properties.parse ("git-ignore-me.properties", { path: true }, function (error, props){
-            return error ? reject(error) : resolve(props);
+        properties.parse('git-ignore-me.properties', { path: true }, function (error, obj) {
+            return error ? reject(error) : resolve(obj);
         });
     });
 
     let result = yield request({
-        uri: props['cloud.uri'] + "/api/charts/popular/",
-        method: "POST",
+        uri: props['cloud.uri'] + '/api/charts/popular/',
+        method: 'POST',
         json: {
             authentication: props['cloud.authentication'],
             limit: props['cloud.limit']
@@ -31,7 +53,7 @@ co(function* () {
 
     for (let i = 0; i < hashes.length; i++) {
         console.log('Downloading script: ' + hashes[i] + ' (' + (i + 1) + '/' + hashes.length + ')');
-        let scriptResult = yield request.get(props['cloud.uri'] + "/inject/" + hashes[i]);
+        let scriptResult = yield request.get(props['cloud.uri'] + '/inject/' + hashes[i]);
         let script = scriptResult.body;
 
         let path = targetDir + hashes[i] + '/';
@@ -46,14 +68,3 @@ co(function* () {
 }).catch(function (err) {
     console.log(err);
 });
-
-function wrap(script) {
-    return "window.addEventListener('DOMContentLoaded', function () {" + script + "});\n";
-}
-
-function html(hash) {
-    return '<script src="https://code.highcharts.com/stock/highstock.js"></script>' +
-        '<script src="https://code.highcharts.com/stock/modules/data.js"></script>' +
-        '<script src="https://code.highcharts.com/stock/modules/exporting.js"></script>' +
-        '<div id="highcharts-' + hash + '"></div>'
-}
diff --git a/utils/samples/compare-iframe.php b/utils/samples/compare-iframe.php
index 0fcfd3f68ee..a3a60ae37ea 100644
--- a/utils/samples/compare-iframe.php
+++ b/utils/samples/compare-iframe.php
@@ -22,11 +22,12 @@
 	$rightPath = vsprintf(isset($_SESSION['rightPath']) ? $_SESSION['rightPath'] : Settings::$rightPath, $topDomain);
 }
 
-// A commit is given, insert the full path
-if (preg_match('/^[a-z0-9]+$/', $leftPath)) {
+// A commit or tag is given, insert the full path
+$commitOrTag = '/^[a-z0-9]+$/';
+if (preg_match($commitOrTag, $leftPath)) {
 	$leftPath = "cache.php?file=http://github.highcharts.com/$leftPath";
 }
-if (preg_match('/^[a-z0-9]+$/', $rightPath)) {
+if (preg_match($commitOrTag, $rightPath)) {
 	$rightPath = "cache.php?file=http://github.highcharts.com/$rightPath";
 }
 
diff --git a/utils/settings.php b/utils/settings.php
index 936aceef763..e6fb2b3319b 100644
--- a/utils/settings.php
+++ b/utils/settings.php
@@ -5,8 +5,13 @@ class Settings {
 	//static $git = "C:\Git\bin\git"; // Typical Windows path
 	static $git = '/usr/local/git/bin/git';
 
+	// Set it to commit id to test against a certain commit. To test against
+	// a certain version, use the version's commit id.
 	static $leftPath = "http://code.highcharts.com";
-	static $rightPath = "http://code.highcharts.%s"; // inserts top domain from utils.highcharts.{whatever}/samples
+	// Inserts top domain from utils.highcharts.{whatever}/samples. 
+	// Set it to commit id to test against a certain commit.
+	static $rightPath = "http://code.highcharts.%s";
+	
 	static $exportServer = "http://export.highcharts.com";
 	static $jQueryVersion = "1.8.3";
 }