FR: Recover Emails Sent to Deactivated Aliases

[kylhuk]

This is a Feature Request based on personal usage of Simple Login for the past few years.

User Story
I as end user would like to receive e-mails which were sent to deactivated aliases, after I activated the alias within a specified amount of time (threshold)

Reason
I use aliases from the past time, where I had only one e-mail address. I am slowly switching to random aliases whenever I see the address is still in use. Many services request you to verify your old e-mail address first. Due to the fact that this address is in many spam lists, it is mostly deactivated. When requesting an e-mail address change from said service, the e-mail gets sent to a deactivated alias. In many cases, those services won't send a second e-mail shortly after to avoid spam. So it would be nice to receive all the e-mails that were sent in the past N minutes.