diff --git a/index.html b/index.html
index ba1cefa..2d7f25a 100644
--- a/index.html
+++ b/index.html
@@ -376,14 +376,21 @@
     </style>
 
     <script type='module'>
-      // TODO remove
+      // Shortcut for log(...) instead of console.log(...)
       window.log = console.log
 
-      import {init} from './src/index.js'
-
-      window.addEventListener('load', () => {
-        init(document.getElementById('app'))
-      })
+      if(new URLSearchParams(window.location.search).get('leporello') == null) {
+        const {init} = await import('./src/index.js');
+        (
+          document.readyState == 'complete'
+            ? Promise.resolve()
+            : new Promise(resolve => 
+                window.addEventListener('load', resolve)
+              )
+        ).then(() => {
+          init(document.getElementById('app'))
+        })
+      }
     </script>
   </head>
 
diff --git a/src/editor/ui.js b/src/editor/ui.js
index 00002e8..af6a7cb 100644
--- a/src/editor/ui.js
+++ b/src/editor/ui.js
@@ -195,14 +195,18 @@ export class UI {
         click: e => e.stopPropagation(),
         change: this.change_entrypoint,
       },
-        Object.keys(state.files).sort().map(f =>
-          el('option', 
-            state.entrypoint == f
-            ? { value: f, selected: true }
-            : { value: f},
-            f == '' ? "*scratch*" : f
+        Object
+          .keys(state.files)
+          .sort()
+          .filter(f => f == '' || f.endsWith('.js') || f.endsWith('.mjs'))
+          .map(f =>
+            el('option', 
+              state.entrypoint == f
+                ? { value: f, selected: true }
+                : { value: f},
+              f == '' ? "*scratch*" : f
+            )
           )
-        )
       )
     )
   }