Strange, works for me, and I have played it on three different days now... However it's a project of another HN user that they only mentioned in another thread, so it might still be work in progress.
Or they didn't want to use cookies for fear of GDPR :) ? But I'm not sure you can get off the GDPR hook by collecting IP addresses instead of setting cookies actually...
Yes, that's why I was moving to LocalStorage based model but this created two different sources of truth which was the whole cause of bug. I'll fix all the issues and delete all data in cloud ASAP. :)