A quote from their blog site: From Yahoo!'s point of view, any type of signed-in user involving with Yahoo! solutions is a valued user, whether she confirms using a Yahoo!, Facebook, or Google ID.
Sign Into Yahoo With Facebook
Login to Yahoo Mail account on PC/Desktop computer
First you require a username and password; now open web browser from your computer/desktop. After that open web page www.yahoomail.com on it. To start their new "one-click" sign-in just click the "Sign in with: Facebook" symbol on the Yahoo! login screen. That's all you need; to get access of your Yahoo mail account.
Login to Yahoo Mail account on Mac computer system
If you are an individual of Mac computer then Safari should be your internet browser. Safari is the most effective surfing option for Mac OS; Safari fasts, quicker as well as easy to use web browser. You can easily access your Yahoo Mail account with it. See, how to login with Yahoo mail account on Safari browser. Just open Safari as well as type www.yahoomail.com; you will be routed to Yahoo mail sign-in web page. To start their brand-new "one-click" sign-in simply click on the "Sign in with: Facebook". You are after that fully authorized into Yahoo!
However, a suggestion- you still will not be able to sign into a mobile or desktop computer client making use of Google OpenID.
I wish this write-up could assist you. Thanks ...