diff --git a/tests/playground.html b/tests/playground.html
index 5443c1ecf..e15ee7684 100644
--- a/tests/playground.html
+++ b/tests/playground.html
@@ -7,9 +7,16 @@
   <!-- This script loads uncompressed when on localhost and loads
        compressed when it is being hosted.  Please add any other
        dependencies to bootstrap.js. -->
+<script>
+  var BLOCKLY_BOOTSTRAP_OPTIONS = {
+    additionalScripts: [
+      'msg/messages.js',
+      'tests/playgrounds/screenshot.js',
+      'node_modules/@blockly/dev-tools/dist/index.js',
+    ],
+  }
+</script>
 <script src="bootstrap.js"></script>
-<script src="playgrounds/screenshot.js"></script>
-<script src="../node_modules/@blockly/dev-tools/dist/index.js"></script>
 <script type=module>
 import Blockly from './blockly.mjs';
 
diff --git a/tests/playgrounds/advanced_playground.html b/tests/playgrounds/advanced_playground.html
index 07eec11db..787cf12ee 100644
--- a/tests/playgrounds/advanced_playground.html
+++ b/tests/playgrounds/advanced_playground.html
@@ -3,11 +3,19 @@
 <head>
 <meta charset="utf-8">
 <title>Advanced Blockly Playground</title>
+
+<script>
+  var BLOCKLY_BOOTSTRAP_OPTIONS = {
+    additionalScripts: [
+      'msg/messages.js',
+      'tests/playgrounds/screenshot.js',
+      'tests/themes/test_themes.js',
+      'node_modules/@blockly/dev-tools/dist/index.js',
+      'node_modules/@blockly/theme-modern/dist/index.js',
+    ],
+  }
+</script>
 <script src="../bootstrap.js"></script>
-<script src="./screenshot.js"></script>
-<script src="../themes/test_themes.js"></script>
-<script src="../../node_modules/@blockly/dev-tools/dist/index.js"></script>
-<script src="../../node_modules/@blockly/theme-modern/dist/index.js"></script>
 
 <script type="module">
 import Blockly from '../blockly.mjs';
