Change 482400 had a related patch set uploaded (by Paladox; owner: Paladox):
[operations/puppet@production] phabricator: Migrate mail config to cluster.mailers

https://gerrit.wikimedia.org/r/482400

they now include "void-recipient@<domain>" in the email https://github.com/phacility/phabricator/blob/73e3057c52f46ec6ddb75fc495a03255c5199c16/src/applications/metamta/storage/PhabricatorMetaMTAMail.php#L1474

Thanks @Paladox, per IRC and Gerrit +1 to that config change. Could you add some info in what version exactly this will switch over to use new config?

It has been removed in version 2019.01 (https://secure.phabricator.com/w/changelog/2019.01/)

https://secure.phabricator.com/book/phabricator/article/configuring_outbound_email/

looked at upstream docs, config change looks ok to me, confirmed with @herron services should use smtp to localhost and this does just that.

paladox tested on wmcs that phabricator still sends out mail and the metamta.* options are unffected, so domain and no-reply@ address are unchanged

Change 482400 merged by Dzahn:
[operations/puppet@production] phabricator: Add new cluster.mailers

https://gerrit.wikimedia.org/r/482400

deployed in production and we tested mail still works. this just adds the new config and does not remove the old config though

Change 489121 had a related patch set uploaded (by Paladox; owner: Paladox):
[operations/puppet@production] phabricator: Remove old mail config

https://gerrit.wikimedia.org/r/489121

Change 489121 merged by Dzahn:
[operations/puppet@production] phabricator: Remove old mail config

https://gerrit.wikimedia.org/r/489121

deployed in production (phab1001) , please test that mail still works

Mentioned in SAL (#wikimedia-operations) [2019-02-14T01:15:14Z] <mutante> phab1001 - phabricator mail config converted to cluster.mailers to adjust to upstream change (T212989)