Cleanup experimental notice

With bootstrap js always included there is no need to add own js to dismiss it.
Only generate the notice for experimental pages, no need to have js for that.

examples/webpack/example-builder.js

@@ -291,15 +291,11 @@ class ExampleBuilder {
     jsSource = jsSource.replace('new Worker()', "new Worker('./worker.js')");
 
     data.js = {
-      tag: `<script src="${this.common}.js"></script><script src="${jsName}"></script>`,
+      tag: `<script src="${this.common}.js"></script>
+        <script src="${jsName}"></script>`,
       source: jsSource,
     };
 
-    if (data.experimental) {
-      const prelude = '<script>window.experimental = true;</script>';
-      data.js.tag = prelude + data.js.tag;
-    }
-
     // check for worker js
     const workerName = `${name}.worker.js`;
     const workerPath = path.join(data.dir, workerName);