Facebook allows you to remotely terminate your active sessions from any terminals (smartphones, PC or tablets) at any moment. So if you are still logged-in on Facebook on another PC /terminal, here's how to sign-out in a few clicks:
- Login to Facebook.
- Click on Account settings > General
- In the right pane, expand the "Active Sessions" section
- As in the figure below, you shall have your"Current Session" and the other active sessions.
- Simply click on "End activity" next to the session of your choice.
- Click on Close to exit,