Opening a project URL you don't have access to now shows a no-access screen in place. It's identical whether or not the project exists, so it can't be used to discover project slugs. If you're signed in, you can switch to one of your own projects from the header.

#Fixes

Reserved usernames: usernames generated during Google sign-in or registration are now checked against reserved route names, such as docs, settings, and dashboard, and the 3–30 character format rules.
Dashboard links: /dashboard/logs, /dashboard/members, /dashboard/tokens, /dashboard/encryption, and /dashboard/settings now forward to the matching page of your active project.
Mistyped URLs: unknown /settings/* and /docs/* URLs now return a real 404 page.

The 404 and error screens were also redesigned, with full site navigation, the requested path, and links to Documentation, Quick Start, and Changelog.