Five hidden signals.

Hints, not solutions. Find them yourself.

1. [1]Type the right four digits anywhere. The city's first error code.—
2. [2]Visit all ten doctrines. The badge knows.—
3. [3]Be here at the moment the daily signal flips. UTC.—
4. [4]A page that 404s. Until it doesn't.—
5. [5]Hold the honoree. Hear their private channel.—

DISCOVERIES LIVE IN YOUR BROWSER. CLEARING STORAGE FORGETS THE CITY.