fix(demo): prevent flash of source bar in hosted envs

Author: grega

docs/index.html

@@ -5,6 +5,16 @@
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>Python Friendly Error Messages - Demo</title>
+  <script>
+    (() => {
+      const localHosts = new Set(['localhost', '127.0.0.1', '::1']);
+      const isLocalDevelopment = window.location.protocol === 'file:' || localHosts.has(window.location.hostname);
+      window.__PFEM_IS_LOCAL_DEVELOPMENT__ = isLocalDevelopment;
+      if (isLocalDevelopment) {
+        document.documentElement.classList.add('demo--local-dev');
+      }
+    })();
+  </script>
   <link rel="stylesheet" href="styles.css">
 </head>
 
@@ -24,8 +34,7 @@ <h1>Python Friendly Error Messages - Demo</h1>
   <script type="module">
     import { examples } from './demo-examples.js';
 
-    const localHosts = new Set(['localhost', '127.0.0.1', '::1']);
-    const isLocalDevelopment = window.location.protocol === 'file:' || localHosts.has(window.location.hostname);
+    const isLocalDevelopment = Boolean(window.__PFEM_IS_LOCAL_DEVELOPMENT__);
 
     const pageParams = new URLSearchParams(window.location.search);
     const useLocal = isLocalDevelopment && pageParams.has('local');

docs/styles.css

@@ -28,11 +28,15 @@ h1 {
   padding: 0.5rem 1rem;
   font-size: 0.85rem;
   font-family: monospace;
-  display: flex;
+  display: none;
   align-items: center;
   margin-bottom: 1.5rem;
 }
 
+.demo--local-dev .demo__source-bar {
+  display: flex;
+}
+
 .demo__source-bar .container {
   display: flex;
   align-items: center;