Easy methods to verify integrity of Electrum pockets created utilizing BIP39 mnemonic?

Given paper backup of 24-word BIP39 mnemonic and passphrase, how can one verify integrity of Electrum pockets given "Pockets" / "Seed" is greyed out?
Given paper backup of 24-word BIP39 mnemonic and passphrase, how can one verify integrity of Electrum pockets given "Pockets" / "Seed" is greyed out?