There are two ways. 1) Sign out when done using a website. 2) Type about:preferences#privacy<enter> in the address box. The button next to History, select Use Custom Settings.

Turn on Remember My Browsing And Download History At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on ONLY Cache and Form And Search History and in your case; Active Logins.

Your first solution worked perfectly Fred. I am very grateful and appreciate that you would do this for me as a Mozilla volunteer. Thank you thank you, and an interesting New Year to you and yours.

Note that "Active Logins" do not apply to normal websites, but are about basic HTML authentication. Normal websites merely use cookies to remember you.

Detail like websites remembering you and log you in automatically is stored in a cookie, so you would have to clear such a cookie to make the website forget about you. Note that best is to logout to clear your session cookie on the server whereas clearing the cookie for this website on your computer doesn't do this, so in theory someone could use your session ID to access the account.

You can use these steps to make a website recognize and remember you.

• create a cookie allow exception with the proper protocol (https:// or http://) to make a website remember you

You can check that you aren't clearing important cookies.

• using "Delete cookies and site data when Firefox is closed" keeps cookies with an allow exception
• using "Clear history when Firefox closes" to clear cookies clears all cookies including cookies with an allow exception you may want to keep
• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exceptions for passwords and other website specific data

• Settings -> Privacy & Security
  Cookies and Site Data: "Manage Exceptions"

Glad to help. Safe Surfing.