A good fix takes time...

Playground/css/index.css

@@ -9,7 +9,33 @@ body {
     overflow: hidden;
     font-family: sans-serif;
 }
+#waitDiv {
+    position: absolute;
+    width: 100%;
+    height: 100%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    background: black;
+    opacity: 0.8;
+    top:0px;
+    left:0px;
+    z-index: 10;
+    flex-direction: column;
+}
 
+#waitSpan {
+    text-align: center;
+    font-size: 20px;
+    font-weight: lighter;
+    color: white;
+}
+
+#waitTitle {
+    text-align: center;
+    font-size: 38px;
+    color: #15A4FA;
+}
 .wrapper {
     height: calc(100% - 40px - 30px); /* nvabar top and bottom*/
     width: 100%;

Playground/index-local.html

@@ -29,7 +29,6 @@
             Babylon.js Playground
         </div>
         <div class="version" id="mainTitle">
-            v3.0-alpha
         </div>
 
         <div class="category">
@@ -347,6 +346,11 @@
         </div>
     </div>
 
+    <div id="waitDiv">
+        <span id="waitTitle">Babylon.js Playground<BR><BR><BR></span>
+        <span id="waitSpan">please wait<br>loading editor...</span>
+    </div>       
+
     <script src="https://code.jquery.com/jquery.js"></script>
 
     <script src="js/actions.js"></script>

Playground/index.html

@@ -65,7 +65,6 @@
             Babylon.js Playground
         </div>
         <div class="version" id="mainTitle">
-            v3.0-alpha
         </div>
 
         <div class="category">
@@ -379,6 +378,11 @@
         </div>
     </div>
 
+    <div id="waitDiv">
+        <span id="waitTitle">Babylon.js Playground<BR><BR><BR></span>
+        <span id="waitSpan">please wait<br>loading editor...</span>
+    </div>   
+
     <script src="https://code.jquery.com/jquery.js"></script>
 
     <script src="js/actions.js"></script>