diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 8fde057..30bf38c 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -435,10 +435,15 @@ function App(): JSX.Element {
       return
     }
 
-    let wsUrl = import.meta.env.CUSTOM_VITE_WS_URL || 'wss://excalidraw.forkless.com'
-    if (wsUrl && !wsUrl.startsWith('ws://') && !wsUrl.startsWith('wss://')) {
-      wsUrl = 'wss://' + wsUrl
+    let rawUrl = import.meta.env.CUSTOM_VITE_WS_URL || 'wss://excalidraw.forkless.com'
+    try {
+      const parsed = new URL(rawUrl.startsWith('ws') ? rawUrl.replace(/^ws/, 'http') : rawUrl)
+      rawUrl = 'wss://' + parsed.host
+    } catch {
+      // Bare hostname/IP — prepend wss://
+      rawUrl = 'wss://' + rawUrl
     }
+    const wsUrl = rawUrl
     
     websocketRef.current = new WebSocket(wsUrl)