> defines unused in some opaque sense where receiving but not sending emails is “unused”
"You are considered active if you log in and use our services once a year. Simply logging in to any Proton service on our web, desktop, or mobile apps at least once a year is enough."
"You are considered active if you log in and use our services once a year. Simply logging in to any Proton service on our web, desktop, or mobile apps at least once a year is enough."
<https://proton.me/support/inactive-accounts>