Update behavior.js

static/behavior.js

@@ -281,7 +281,7 @@ document.addEventListener("DOMContentLoaded", function() {
     }
 
     if (typeof io !== "undefined") {
-        websocket_connection = io();
+        websocket_connection = io({ transports: ["polling"], upgrade: false });
         
         websocket_connection.on("game_state_changed", function() {
             if (document.querySelector(".game-section") || document.querySelector(".administrator-section")) {