Currently, Bitwarden allows one to register one email address that is used for sending notifications of logins from new devices, reporting failed attempts, sending Bitwarden announcements, etc.
Allowing one to specify additional emails beyond just the one used to login to the vault would help prevent lockout if an email provider ceases operation in one or more countries. This is not just a theoretical risk, given this headline today:
Indian court orders blocking of Proton Mail
A court in India has ordered the blocking of encrypted email provider Proton Mail across the country.
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This is the latest legal tussle facing Proton Mail in India, its second ruling in as many years aimed at blocking the encrypted email service from operating in the country.
Additionally, the same list ought to be used for email-based two-step-login to mitigate the same risk there.