2 years ago when I got a new phone, I had to re-register in both WhatsApp and Signal.
Both send you a code over SMS. I hate giving apps SMS access, so I refuse SMS intercept permission when an app asks for it, and instead I manually enter the received code in the app.
This was possible in WhatsApp, but was not possible in Signal. It won't allow you. You must give it SMS access to read the code. So much for privacy/security/... Only app I use which didn't allow me to manually enter the SMS code.
Both send you a code over SMS. I hate giving apps SMS access, so I refuse SMS intercept permission when an app asks for it, and instead I manually enter the received code in the app.
This was possible in WhatsApp, but was not possible in Signal. It won't allow you. You must give it SMS access to read the code. So much for privacy/security/... Only app I use which didn't allow me to manually enter the SMS code.