The auto login is controlled by cookies. If you don't select the remember me box, the session should expire when you close your browser session. Here is a detailed guide to how it works:
From Confluence Cookies:
The JSESSIONID cookie is created by the application server and used for session tracking purposes. This cookie contains a random string and the cookie expires at the end of every session or when the browser is closed.
The 'remember me' cookie, seraph.confluence, is generated by Confluence when the user selects the Remember me check box on the login page.
When using an Atlassian account that is not managed, it’s possible to change the email address, but we often receive the following notification on the email that we want to use: Sorry, we couldn'...
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