On https://secure.phabricator.com/settings/panel/emailpreferences/ I set months ago
Maniphest Tasks: | ⚪ Ignore | A task's subscribers change.
Still I receive email notifications about "[Changed Subscribers]" (no other actions involved or listed in the notification email). Latest example is https://secure.phabricator.com/T4171#140456
Note that I am a "watcher" of the "Wikimedia" project which is associated to https://secure.phabricator.com/T4171
I consider this unexpected behavior.
I have checked that I have only one email address configured and it is for my account @aklapper hence no other potential second account involved here.