diff --git a/src/playground/index.ejs b/src/playground/index.ejs
index d63e7eb026e..baeeed9fc69 100644
--- a/src/playground/index.ejs
+++ b/src/playground/index.ejs
@@ -37,6 +37,7 @@
     </style>
   </head>
   <body>
+    <% if (htmlWebpackPlugin.options.pwa) { %>
     <script>
       if ('serviceWorker' in navigator) {
         window.addEventListener('load', function () {
@@ -52,5 +53,25 @@
         console.log('Service Worker is not supported by browser.');
       }
     </script>
+    <% } else { %>
+    <script>
+      if ('serviceWorker' in navigator) {
+        window.addEventListener('load', function () {
+          navigator.serviceWorker.getRegistration('./service-worker.js').then(function (registration) {
+            if (registration) {
+              console.log('found PWA worker registration', registration.scope);
+              registration.unregister().then(function (result) {
+                console.log('PWA worker unregister', result);
+              });
+            } else {
+              console.log('no PWA worker registration');
+            }
+          });
+        });
+      } else {
+        console.log('Service Worker is not supported by browser.');
+      }
+    </script>
+    <% } %>
   </body>
 </html>
diff --git a/webpack.config.js b/webpack.config.js
index 55627e0c8a0..5cdc444040a 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -117,21 +117,24 @@ const buildConfig = baseConfig.clone()
         chunks: ['gui'],
         template: 'src/playground/index.ejs',
         title: 'Smalruby',
-        originTrials: JSON.parse(fs.readFileSync(path.resolve(__dirname, 'origin-trials.json')))
+        originTrials: JSON.parse(fs.readFileSync('origin-trials.json')),
+        pwa: process.env.NODE_ENV === 'production'
     }))
     .addPlugin(new HtmlWebpackPlugin({
         chunks: ['gui'],
         template: 'src/playground/index.ejs',
         filename: 'ja.html',
         title: 'スモウルビー',
-        originTrials: JSON.parse(fs.readFileSync(path.resolve(__dirname, 'origin-trials.json')))
+        originTrials: JSON.parse(fs.readFileSync('origin-trials.json')),
+        pwa: process.env.NODE_ENV === 'production'
     }))
     .addPlugin(new HtmlWebpackPlugin({
         chunks: ['player'],
         filename: 'player.html',
         template: 'src/playground/index.ejs',
         title: 'Smalruby: Player Example',
-        originTrials: JSON.parse(fs.readFileSync(path.resolve(__dirname, 'origin-trials.json')))
+        originTrials: JSON.parse(fs.readFileSync('origin-trials.json')),
+        pwa: process.env.NODE_ENV === 'production'
     }))
     .addPlugin(new CopyWebpackPlugin({
         patterns: [
@@ -145,7 +148,9 @@ const buildConfig = baseConfig.clone()
                 context: 'src/examples'
             }
         ]
-    }))
+    }));
+
+const buildWithPwaConfig = buildConfig.clone()
     .addPlugin(
         new WorkboxPlugin.GenerateSW({
             disableDevLogs: !process.env.DEBUG,
@@ -188,5 +193,5 @@ const buildConfig = baseConfig.clone()
 const buildDist = process.env.NODE_ENV === 'production' || process.env.BUILD_MODE === 'dist';
 
 module.exports = buildDist ?
-    [buildConfig.get(), distConfig.get()] :
+    [buildWithPwaConfig.get(), distConfig.get()] :
     buildConfig.get();
