Bip39 Checksum. Press X to abort passphrase software and continue to keep editing the passphrase. Choosing CANCEL immediately after an abort will stop the process. By using a passphrase, you incorporate an extra layer of protection to your wallet, shielding your resources regardless of whether your seed phrase is compromised. https://210list.com/story19181261/bip39-passphrase-https-linktr-ee-bip39-a-simple-key-for-bip39-unveiled