Your credential is your lightning key pair. If you restore another wallet from the same seed, your credentials can follow you to any wallet.
Bummer. Tried Muun and Wallet of Satoshi and finally d/led Breez because it has lnurl support (unnecessarily?) I don’t even have sats in it, but it logged me in and apparently there’s no way to access private keys in Breez. hrmph.
I'm surprised Breez doesn't have you backup your seed. I could've swore I had to.