I'm a developer for Firefox Relay. Back in 2021, we took over the mozmail.com domain for our aliases. We are operating Relay with a number of features that I think mitigate the risks that these aliases pose:
Bounces & deliver-ability - if our user disables an @mozmail.com alias, we DO NOT trigger a bounce. Instead, we silently drop the email.
Anti-abuse protections - we limit our free users to 5 total aliases, and we rate-limit our premium customers so they cannot create large-scale throw-away aliases for abusive sign-ups and behaviors.
I'm a developer for Firefox Relay. Back in 2021, we took over the
mozmail.com
domain for our aliases. We are operating Relay with a number of features that I think mitigate the risks that these aliases pose:It looks like
mozmail.com
is added because it is on https://raw.githubusercontent.com/andreis/disposable-email-domains/master/domains.txt. This repo now redirects to https://github.com/disposable/disposable-email-domains. I've opened https://github.com/disposable/disposable/issues/97 to remove it there, along with a PR to add it to their whitelist.