Apple has never gotten it's mail system working properly, fair enough, as integrated into the system as this is, so be it.
None the less I've found over the last couple months, and gaining, in the 'mail activity' field "incoming mail" is displayed, dozens of times per day random alphanumeric values separated by a dash.
This is outside of the normal incoming mail. I've checked junk folders directly after these ghostly 'messages' and nothing.
Thought about packet capture, though with all the network activity, sifting through is a job for someone that has nothing better to do. Though if my only choice.
It would appear something of the sort [4y47ruwuw84i239u-88f8whje7wgf9]
Idea's ?