I had a complaint from a user who told me email notifications for direct mentions were being sent despite it being disabled in profile. I checked mongo, and here's what's in the database:
{ "_id" : "...",
"emails" : [ { "address" : "REDACTED", "verified" : true } ],
"settings" : { "preferences" : { "emailNotificationMode" : "disabled", },
}
Looks like something is ignoring that preference.