diff --git a/config/examples/example.html b/config/examples/example.html
index a90b691dc4..6981f73b6e 100644
--- a/config/examples/example.html
+++ b/config/examples/example.html
@@ -11,7 +11,7 @@
     <link rel="stylesheet" href="./resources/layout.css" type="text/css">
     {{{ extraHead.local }}}
     {{{ css.tag }}}
-    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=fetch,requestAnimationFrame"></script>
+    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=fetch,requestAnimationFrame,Element.prototype.classList"></script>
     <script src="./resources/zeroclipboard/ZeroClipboard.min.js"></script>
     <title>{{ title }}</title>
   </head>
diff --git a/test/index.html b/test/index.html
index 3d461b2021..0426864072 100644
--- a/test/index.html
+++ b/test/index.html
@@ -15,7 +15,7 @@
   <script type="text/javascript" src="../node_modules/mocha/mocha.js"></script>
   <script type="text/javascript" src="../node_modules/proj4/dist/proj4.js"></script>
   <script type="text/javascript" src="test-extensions.js"></script>
-  <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame"></script>
+  <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList"></script>
   <script>
     if (typeof initMochaPhantomJS === 'function') {
       initMochaPhantomJS()
diff --git a/test_rendering/index.html b/test_rendering/index.html
index b62179a0c1..37fad198d5 100644
--- a/test_rendering/index.html
+++ b/test_rendering/index.html
@@ -16,7 +16,7 @@
   <script type="text/javascript" src="../node_modules/proj4/dist/proj4.js"></script>
   <script type="text/javascript" src="../node_modules/resemblejs/resemble.js"></script>
   <script type="text/javascript" src="../test/test-extensions.js"></script>
-  <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame"></script>
+  <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList"></script>
   <script>
     mocha.setup({
       ui: 'bdd',