Yes, unfortunately it is happening on a new installation.
I deleted the database and files, re-installed the latest beta and got the same error going to the demo forum.
I've made zero changes, I simply clicked the "go to the suite" button.
It briefly shows the forum, gives the JS error I posted above then redirects to my live site's 404 page but with this url (I've redacted the actual domain):
https://www.mydomain.com/devcommunity/community/static/js/cloud/front_front_realtime.js?v=166982fc561734310691&csrfKey=&antiCache=166982fc561734310691
Live site is at /public_html/community
Test site is at /public_html/devcommunity/community
PHP version 8.1.
Nothing in the system or error logs.
I've updated my dev site login details so you can have a look if you like.