Summary: Setting null as an array key is deprecated since PHP 8.5 per https://www.php.net/releases/8.5/en.php: "Using null as an array offset or when calling array_key_exists() is now deprecated. Use an empty string instead." ``` ERROR 8192: Using null as an array offset is deprecated, use an empty string instead at [/var/www/html/phorge/phorge/src/applications/metamta/query/PhabricatorMetaMTAMemberQuery.php:132] ``` Closes T16367 Test Plan: Go to a user profile page, select "Send Welcome Email", click "Send Email". Reviewers: O1 Blessed Committers, avivey Reviewed By: O1 Blessed Committers, avivey Subscribers: avivey, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno Maniphest Tasks: T16367 Differential Revision: https://we.phorge.it/D26538