Install Vercel Speed Insights

index.html

@@ -249,5 +249,6 @@ <h2 id="watchTitle">Title</h2>
 
     <script src="update-manager.js?v=142"></script>
     <script src="app.js?v=142"></script>
+    <script src="speed-insights.js?v=142"></script>
   </body>
 </html>

package.json

@@ -21,5 +21,8 @@
   "license": "MIT",
   "engines": {
     "node": ">=18.0.0"
+  },
+  "dependencies": {
+    "@vercel/speed-insights": "^2.0.0"
   }
 }

speed-insights.js

@@ -0,0 +1,50 @@
+/**
+ * Vercel Speed Insights Integration
+ * 
+ * Initializes Vercel Speed Insights for performance monitoring.
+ * This script is loaded after the main app initialization.
+ */
+
+(function() {
+  'use strict';
+
+  // Initialize the Speed Insights queue
+  window.si = window.si || function() {
+    (window.siq = window.siq || []).push(arguments);
+  };
+
+  // Load the Speed Insights script
+  function loadSpeedInsights() {
+    // Check if script is already loaded
+    const existingScript = document.querySelector('script[src*="speed-insights"]');
+    if (existingScript) {
+      return;
+    }
+
+    // Create script element
+    const script = document.createElement('script');
+
+    // Use the Vercel-hosted script
+    script.src = '/_vercel/speed-insights/script.js';
+    script.defer = true;
+
+    // Add SDK information
+    script.dataset.sdkn = '@vercel/speed-insights';
+    script.dataset.sdkv = '2.0.0';
+
+    // Handle load errors
+    script.onerror = function() {
+      console.warn('[Vercel Speed Insights] Failed to load script. This is expected in local development.');
+    };
+
+    // Append to document head
+    document.head.appendChild(script);
+  }
+
+  // Load when DOM is ready
+  if (document.readyState === 'loading') {
+    document.addEventListener('DOMContentLoaded', loadSpeedInsights);
+  } else {
+    loadSpeedInsights();
+  }
+})();