Yahoo should not keep me logged-in
Yahoo keeps me logged into the site even though I've explicitly told it not to remember me. To not remember me, in my mind, means they won't keep me logged in and will prompt me again for my credentials when accessing any of their services via a NEW session. Yahoo has, to date, not amended this issue and it's become a real hassle for me because Yahoo thinks they're safe now. If I uncheck "Remember me", I expect Yahoo to store cookies but to also then require disabling this whole SSO and federation **** that utilizes tokens across sessions.

Hi there!
Have you tried clearing your browser’s cache and cookies? https://help.yahoo.com/kb/SLN2891.html?redirect=true
Regards,
Mail Support