Vault Timeout Options
Vault Timeout determines how your Vault will behave after a specified period of inactivity. Timeout is configured individually for each Bitwarden Client application be it your Web Vault, Browser Extension, Desktop or Mobile.
Enabling the Vault Timeout policy will implement a maximum Vault Timeout duration for all members of your Organization. This policy applies the timeout restriction to all client applications (Mobile, Desktop, Browser Extension, etc.). Before you can enable the Vault Timeout policy, the Single Organization policy must be enabled. Conversely, the Vault Timeout policy must be disabled prior to disabling the Single Organization policy.
Once the user-selected timeout has been reached, you can select if you want your vault to either lock or log out.
Locking your vault is the default Timeout action. Locking your vault allows you to access your data again by entering your Master Password (this method is available on all clients), entering a user-created PIN (this method is available on all clients except the CLI), or Authenticate using Biometrics This is available with compatible hardware on Desktop, Browser and Mobile. No internet connection is required to access a Locked vault.
Selecting the Log Out option in the vault timeout settings provides additional protection for your vault. When the timeout period has occurred, the client is logged out, removing the encrypted data from your device. To log back into your vault, users must provide their Bitwarden email address, their master password, and their two-step login method.
Web and Browser Extension Timeouts
The Bitwarden Web Vault and Browser Extension clients are dependent on your web browser. If you refresh your browser, your Web Vault will lock.
Refreshing your browser will not affect the Browser Extension. If you close your browser tab, you will be logged out of your Web Vault. Closing a single tab will not affect a Browser Extension.
If you close your browser, you will be logged out of both your Web Vault and Browser Extension.A tip for users, if you are using a Browser Extensions, you can bypass this by enabling the Unlock with PIN option and uncheck the Lock with Master Password on browser restart checkbox.
Reference: Unlock Options Per Client
On your screen is a chart of Vault Timeout Options per Client.