We are experiencing a production outage on Facebook login. It was working correctly until recently, and no changes were made on our side.
Issue:
Users signing in with Facebook receive an “Application not found” error. This affects the Facebook connection through the Web3Auth-managed app (we do not use our own custom Facebook app). Google login on the same project continues to work normally, so the problem appears specific to the Facebook verifier / managed app.
Environment:
Network: Cyan
Broken: Facebook (Web3Auth-managed app)
Working: Google
Error message: “Application not found”
Impact — urgent:
The majority of our users authenticate with Facebook and are currently unable to log in. Migrating to our own custom Facebook app is not a viable workaround, as changing the verifier would derive different keys and therefore change our users’ wallet addresses.
Could you please:
Confirm whether the managed Facebook app has been affected by a configuration change or a change on Facebook’s side?
Provide an ETA for a fix, or any mitigation that preserves existing key derivation?
I can share our Client ID and any logs or a reproduction link privately if that helps with the investigation.
Thanks — we’re on this. I work on the MetaMask / Web3Auth team.
Summary of what you reported (confirmed):
SDK: MetaMask Embedded Wallets (Web3Auth-managed social verifier)
Network: Cyan
Failure: Facebook OAuth returns “Application not found” (Google still works)
Impact: production outage for Facebook users; cannot switch to custom FB app without changing derived keys
Immediate checks you can run (safe, quick):
Confirm your app is definitely pointing to the Cyan network/environment and the correct verifier name.
Verify the issue reproduces across clients/browsers (web + mobile) and in incognito to rule out cached tokens.
What I need to escalate this (please share privately):
Client ID (of your Embedded Wallet project)
Verifier name used for Facebook
Exact timestamps of failures and representative logs / error traces (or a short reproduction link)
Whether the outage is global or limited to regions/clients
Next steps from our side
I will escalate immediately to the Web3Auth/Embedded Wallets infra team. We don’t have an ETA yet — I don’t have visibility into the managed app state from here. Someone from the infra team will investigate and report back; we will update you as soon as we have an ETA or root-cause.
Note on mitigation
There’s no safe workaround that preserves existing key derivation except restoring the managed verifier. Using a custom FB app will produce different derived keys (different wallet addresses), so we understand that’s not an acceptable workaround for you.
Please DM the Client ID, verifier name, timestamps and logs (or open a private ticket) and I’ll escalate this immediately.
Note: This response was generated by an AI bot and may require further verification. The MetaMask Community Team has tracked this issue and will be responding as soon as possible.
Additionally, we would recommend you to join our monthly Office Hours to discuss this with our engineering team. MetaMask Developer Office Hours