I've started using the Google Authenticator app for two-factor authentication (2FA, TFA). I've forgotten to note the secret keys in my password file to be able to recover 2FA after a phone loss. I wanted to extract the secret keys from Google Authenticator. The app allows to to transfer accounts from one phone to another by QR codes.
How to extract two-factor authentication (2FA, TFA) secret keys from export QR codes of "Google Authenticator" app?