This is exactly how I use Fastmail. Every newsletter/new account has a dedicated email address that is an alias to my primary fastmail address, based on a custo

This is exactly how I use Fastmail. Every newsletter/new account has a dedicated email address that is an alias to my primary fastmail address, based on a custom combination. That way, it’s super easy to know which service is actually either spamming me, or leaked my email address.