We made a UI change recently that may affect those of you trying to automate the client.
Previously, you could create an account with the ACME server by using
--email "" or by choosing “cancel” when prompted for an e-mail. This is no longer the case.
Instead, if you want to create an account without an e-mail address,
--register-unsafely-without-email must be included on the command line. If this flag is included, there will be no prompt for an e-mail address.
--register-unsafely-without-email is highly discouraged. See the
--help all output of the client for more information.