Downgrade playwright to 1.50.0 to fix version mismatch with browserless server

scripts/upload_cookies.py

@@ -54,11 +54,15 @@ def main():
 
     print(f"Sending cookies to {mcp_endpoint}...")
     
+    headers = {
+        "Accept": "application/json, text/event-stream"
+    }
+    
     try:
         # Note: We use a POST to the /mcp endpoint. 
         # In SSE mode, the real endpoint is often dynamic, but many FastMCP 
         # wrappers handle direct POSTs for automation.
-        response = httpx.post(mcp_endpoint, json=payload, timeout=60.0)
+        response = httpx.post(mcp_endpoint, json=payload, headers=headers, timeout=60.0)
         
         if response.status_code == 200:
             result = response.json()