Sessions & logging out
Logging out ends your session everywhere and clears your unlocked data. Here's exactly what it does.
1Log out
The Log out button in the sidebar signs out every device at once, clears the convenience unlock cache, and forgets any devices you'd told to remember your two-factor code.
2Sign out other devices
To end other sessions without logging yourself out here, use Sign out other devices on Security & keys.

3After logging out
To get back in you'll need your password, then your Account Key to unlock again.