Websites generally keep you logged in by setting a cookie. Then when Firefox requests any files from that server, it sends the server back its cookies so the server can verify that you should be able to access those files. You can set Firefox to expire cookies when you exit out of it. There are a few steps to this: '''(1) Set your privacy preference on the Options page''' "3-bar" menu button (or Tools menu) > Options In the left column, click Privacy. Then on the right side, if you do not see detailed settings for cookies, change the selector from "Firefox will: Remember history" to "Firefox will: Use custom settings for history" Then change the cookie lifetime setting from "Keep until: they expire" to "Keep until: I close Firefox". '''(2) Clear existing cookies before exiting''' Before closing Firefox, you can use the "Clear Recent History" feature to remove the existing cookies. You can call that up from the History menu, or press Ctrl+Shift+Delete. If necessary, expand the Details panel so you can uncheck everything but Cookies. Then with the time range set to Everything, click Clear Now. '''(3) Keep session cookies out of Firefox's session history file''' When you have Firefox restore your previous session windows and tabs, it uses the cookies from that time. To prevent that, you can make a settings change as follows: (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button promising to be careful. (2) In the search box above the list, type or paste '''sess''' and pause while the list is filtered (3) Double-click the '''browser.sessionstore.privacy_level''' preference and enter the desired value: * 0 = retain session cookies for all sites in session history (default) * 1 = retain session cookies for HTTP sites in session history, but not HTTPS sites '''(I suggest trying this one)''' * 2 = do not retain session cookies for any sites in session history I think that should cover it!