I am not sure what you mean by secret chat, but this implements NIP24. It's not a hidden secret, it's full on privacy. The only way to decide it is if your private key leaks, not if the chat secret leaks.
Discussion
Thanks, i was confused with the private chat group vs. Incognito option when messaging a person.
It would be cool to set a default option (incognito vs. Not incognito) so that if it was important to you, you dont accidentally do a non- incognito message 🤙
It is the default if you already talked with the other person on the new system. However since not many other clients have coded the new system, it's still not the default