Trezor is considering making larger, safer stateless signatures the default if Bitcoin adopts SHRINCS, a proposed post-quantum signature scheme. CTO Tomáš Sušánka said the smaller stateful option could sit behind advanced settings because reusing its one-time keys can reveal enough information to forge a signature and steal funds. Stateless signatures avoid that reuse risk but could raise fees and slow signing; Trezor has not announced a final setting.
Sušánka said hardware wallets would also need post-quantum protection for firmware and device authentication. Trezor already ships devices that support post-quantum cryptography for wallet authentication, but transactions on them will not be quantum-secure unless Bitcoin itself upgrades.
