I would like to request the ability to configure ProtonMail accounts to use YubiKey-only MFA, with the option to disable soft token authentication.

This feature is particularly important for high‑sensitivity individuals, such as myself serving as a diplomat for a large country, where maximum account security is essential.

Google already supports YubiKey-only MFA, and I would prefer to switch to ProtonMail for its overall security model. Adding this feature would make ProtonMail a stronger choice for users who require hardware‑based authentication exclusively.