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Licensed users can click a Log out from Atlassian button, which redirects them to the Atlassian log-out page.
JSM customer users are instructed how to log out from the JSM customer portal. Clicking the Continue button takes them to the portal in Atlassian, where they have to log out by clicking their profile icon in the top-right of the screen.
Enable the Log out from Atlassian prompt
Go to the Refined Administration.
Click Sites in the left-hand menu.
Pick the site you want to work with.
Go to the Configuration tab.
Scroll down to the Security heading > toggle on Log out from Atlassian prompt.