I would like the option to set a default expiration time for all outgoing emails.

While it's already possible to manually set an expiration date on individual messages, it's easy to forget to do so before sending. A global setting would allow users to automatically apply an expiration period (for example, one year) to every email they send.

Users who enable this feature could still adjust or disable the expiration time on a per-email basis when needed. This would provide a convenient privacy-focused default while maintaining flexibility for exceptions.