diff --git a/tools/wave/www/index.html b/tools/wave/www/index.html
index e727b9ae40..05dcd01cb4 100644
--- a/tools/wave/www/index.html
+++ b/tools/wave/www/index.html
@@ -10,6 +10,7 @@
     <script src="lib/wave-service.js"></script>
     <script src="lib/davidshimjs/qrcode.js"></script>
     <script src="lib/hbbtv.js"></script>
+    <script src="lib/ui.js"></script>
   </head>
 
   <body>
@@ -31,6 +32,7 @@ <h1 class="title is-spaced">
       </div>
 
       <div class="container" style="margin-top: 2em;">
+        <p id="mse-warning" style="max-width: 49em; margin-bottom: 1rem;"></p>
         <h2 class="title is-5">
           New test session
         </h2>
@@ -157,6 +159,19 @@ <h2 class="title is-5">
         addClass(tabbables[selectedTabbable], "focused");
       }
 
+      function createErrorMessage(message) {
+        return {
+          element: "article",
+          className: "message is-warning",
+          children: [
+            {
+              className: "message-body",
+              text: message,
+            },
+          ],
+        };
+      }
+
       function focusNext() {
         skipFocus(1);
       }
@@ -236,6 +251,21 @@ <h2 class="title is-5">
             expiaryDateElement.innerText = config.expirationDate.toLocaleString();
           });
 
+          var mseWarningElement = UI.getElement("mse-warning");
+          if (!mseWarningElement) return;
+          mseWarningElement.innerHTML = "";
+
+          if (!('MediaSource' in window) && !('MediaKeys' in window)) {
+            var error = createErrorMessage('Warning: MSE and EME APIs are not supported');
+            mseWarningElement.appendChild(UI.createElement(error));
+          } else if (!('MediaSource' in window)) {
+            var error = createErrorMessage('Warning: MSE API is not supported');
+            mseWarningElement.appendChild(UI.createElement(error));
+          } else if (!('MediaKeys' in window)) {
+            var error = createErrorMessage('Warning: EME API is not supported');
+            mseWarningElement.appendChild(UI.createElement(error));
+          }
+
           var configurationUrl =
             location.origin +
             WEB_ROOT +
