The “Sign up” link found in the dropdown menu top left, i.e.:
Leads to https://hyperweb.space/sign-up which gives a 404 page:
404 Not Found
Message: The specified key does not exist.
In itself this is fine, and things like that are to be expected in beta software, but still I suggest making a slightly better 404 page to help users distinguish between “feature doesn’t exist yet” and “you’ve found a bug!”, or even have links like that (where you know it’ll point to an actual feature in the future) have them point to an actual info page.