Load toastify before its users.

static/sfu.html

@@ -180,7 +180,7 @@
     </div>
 
     <script src="/protocol.js" defer></script>
-    <script src="/sfu.js" defer></script>
     <script src="/scripts/toastify.js" defer></script>
+    <script src="/sfu.js" defer></script>
   </body>
 </html>