The app address is the address where you did the setup, or the APP_ORIGIN secret when you set one. It sets the cookie host, the allowed Origin, the passkey relying party, the OAuth issuer, and the MCP endpoint.
- Add the new hostname as a Custom Domain of the Worker: Workers & Pages → flared → Settings → Domains & Routes → Add → Custom Domain. The zone must be on Cloudflare in the same account.
- Set the
APP_ORIGINsecret to the new address, such ashttps://links.example.com: Settings → Variables and Secrets → Add, type Secret. A secret change deploys a new version. - Open
https://links.example.com/app/loginand sign in with your username and password.
Until that sign-in, the new address shows only the sign-in page and a notice about the move. A wrong value loses nothing: set APP_ORIGIN back, or delete it if you had none, and deploy again.
The first password sign-in at the new address ends, in one step:
- every other session;
- every connected app (OAuth grant), because the issuer changed;
- every passkey, because passkeys belong to the old address. Add them again in Settings → Security.
API tokens keep working.
Links on the old address keep working. The old address stays a short-link domain, and its app paths redirect to the new address. Do not turn off workers.dev for the Worker if you shared links on it.