Is the Password Manager enabled? *Options/Preferences -> Privacy & Security: Logins: "Remember logins for sites" Make sure you do not run Firefox in permanent Private Browsing mode (Always use Private Browsing mode; Never Remember History). *https://support.mozilla.org/en-US/kb/Private+Browsing *Options/Preferences -> Privacy -> Firefox will: "Use custom settings for history" *remove checkmark: [ ] "Always use Private Browsing mode" ---- A detail like a website remembering you (log you in automatically) is stored in a cookie. You can use these steps to make a website recognize and remember you: *you can create an "Allow" exception to keep specific cookies, especially in case of secure websites and when cookies expire when Firefox is closed. *Options/Preferences -> Privacy & Security -> Cached Web Content: "Clear Now": Exceptions If you remove the cookies from a website then the website will forget about you.