Today I got one of these Letsencrypt Expiry mails again. It looks like this:
Your certificate (or certificates) for the names listed below will expire in 19 days (on 21 Jun 17 19:38 +0000). Please make sure to renew your certificate before then, or visitors to your website will encounter errors. [domain here] ... If you want to stop receiving all email from this address, click [link here] (Warning: this is a one-click action that cannot be undone)
I don't need this particular domain anymore. I understand that the unsubscribe is a one-click action. But does it unsubscribe from this domain only or from all my domains?
According to @pfg at the letsencrypt forum it will unsubscribe for all mailings for all domains for this e-mail address.
Okay, not clicking it then.