Is a streaming session immediately ended and cleaned up on web browser closure? Or does the user have to explicitly log out?

The streaming session ends when the user closes their tab, loads a different page, refreshes the page, or the session times out due to inactivity. For more information about managing your session inactivity timeout, please see our documentation.

There is no need to explicitly log out for the session to end and the device on which the session was running to be factory reset.