Codex App retains the same device instance identity after migrating/cloning a Mac

What version of the Codex App are you using (From “About Codex” dialog)?

26.730.61639 (6234)

What subscription do you have?

Unknown / signed-in ChatGPT account

What platform is your computer?

Darwin 24.6.0 arm64 arm
macOS 15.7.5 (24G624)

What issue are you seeing?

After migrating/copying one Mac's data to another Mac, the Codex app installations on the two computers appear to be treated as the same app/device instance.

The migration seems to copy a persistent local instance/device identifier. As a result, the original and copied installations are not recognized as two independent computers.

What steps can reproduce the bug?

1. Install and sign in to the Codex app on Mac A.
2. Copy or migrate Mac A's user/app data to Mac B (for example, through a full-computer migration/clone).
3. Launch Codex on Mac B using the migrated data.
4. Continue using Codex on both Mac A and Mac B.
5. Observe that the two installations appear to share the same instance identity instead of being independently registered.

What is the expected behavior?

On first launch after a machine migration, Codex should detect that it is running on different hardware and generate a new local instance/device identifier, while preserving account-level synced data such as conversation history.

There should also be a documented and safe way to reset only the local device/instance identity without deleting cloud conversations or unrelated credentials.

Additional information

Reinstalling alone may not resolve this if the copied identity is retained in migrated application data or macOS Keychain. Please ensure the identifier is not derived solely from clonable state, or validate it against the current machine before reuse.

The reporter's original description was: “After copying the previous computer to this computer, ChatGPT/Codex on both computers considers them the same instance.”