title: Yahoo account remains open after using openID to login.why?
body: <p>i have added openid login with Yahoo! and Google in my site.
  it is ok and works fine.</p>
  
  <p>when users select for example Yahoo! to login to my site, they will be logged in in their yahoo mail account too.</p>
  
  <p>i think it is not secure because maybe they don't notice to this issue and leave computer while their email account is availble.</p>
  
  <p>what do you think about this and what is your solution for your own sites?
  as i notice the same story is for stackoverflow.com.</p>