moved to before-unload event

js/main.js

@@ -1,5 +1,5 @@
 // Handle server connection
-document.body.onunload = () => {
+window.addEventListener('beforeunload', () => {
     if (user.connected)
         fetch('/disconnect', {
             method: 'POST',
@@ -11,7 +11,7 @@ document.body.onunload = () => {
                 id: user.id
             })
         }).then(res => {});
-};
+});
 fetch('/connect').then(res => {
     if (res.status === 200) {
         user.connected = true;