I see them with this search.
https://www.google.com/search?q=Address+incorrect+mail+counts+in+Apple%27s+Mail&ie=utf-8&oe=utf-8
I had this problem in Yosemite and I was hoping it would be fixed with an upgrade to El Capitan but it wasn't.
Despite setting the requirement in Mail preferences, Mail does not show in the Dock a count of unread messages.
Is there a fix for this?
michael

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