Ambire Wallet extension allows you to set the "auto-lock" timer. "Locked" extension means that you have to use your "Device Password"/"Biometrics unlock" in order to access your account(s).
By default, the option is set to "Never", meaning that the extension won't lock until you close the browser, or manually open the "Settings" menu and use the "Lock Wallet" option at the bottom of the list:
Important note: This option works great with "View-only" and "Hardware wallet" accounts, but if you import an accounts with private key or recovery phrase, we do recommend to use the shortest time-locks, and to make sure you always manually lock your extension, before leaving the device.
To set the auto-lock timer, please, navigate to "Settings" -> "General" and use the drop down menu next to "Auto-lock device":
