All mail Is Priority Mail
Why does the New Yahoo Mail default to "Priority" Mail first? Every piece of e-mail you receive is "Priority". The New Yahoo Mail should default to "All" first. We will see the "Priority" mail in the list of "All" mail anyway. When the New Yahoo Mail defaults to "Priority" first, you are led to believe you only have, for example, five e-mail delivered. You switch over to "All" and you find you have fifteen e-mail which needs your attention and action. If necessary, why not just make "Priority" mail a bold font or highlighted with a color tint of some kind.

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We encourage you to read at the top of the Uservoice header (forum). There we provide What’s New, Coming Soon and some Tips. There we mention how to disable Inbox Categories: All, Priority, etc. Definitely read those as we update them with useful information. Thanks.