We now have added targeting by opt-in source for Messenger! This includes our opt-in tools and "Other source" which covers any other way someone could opt-in to the Messenger bot. Props @roman!https://d.pr/i/ZABPX6
https://d.pr/i/KPKHmJImportant note: We are only able to track as of the deploy (today) so while we will update help articles etc. I would wait to proactively announce this to customers for a while (at least a week. Maybe 30 days).