Maybe a fix

public/script.js

@@ -1,6 +1,6 @@
 import moment from "https://jspm.dev/moment"
 import { io } from "https://cdn.socket.io/4.3.2/socket.io.esm.min.js"
-const socket = io()
+const socket = io("/", { path: "/foo" })
 const messageButton = document.querySelector("#send")
 const menuButton = document.querySelector("#menu")
 const nameButton = document.querySelector("#name")

server.js

@@ -8,6 +8,7 @@ const io = require("socket.io")(server, {
             "http://192.168.1.226:3000",
             "https://chat.henryhiles.com",
         ],
+        path: "/foo",
     },
 })