firefox 15 does not remember auto logins and bank security questions and my sign in seal for yahoo mail.
have tried going to tools>options>privacy and used custom setting for cookies and it still did not help
my bank and yahoo are listed in the cookies list
Websites remembering you and automatically log you on is stored in a cookie.
Try to remove Cookies from sites causing problems:
Make sure that you do not run Firefox in permanent Private Browsing mode.
To see all History and Cookie settings, choose:
Such issues can be caused by corrupted cookies or cookies that aren't send or otherwise blocked.