In the payload for the app_deauthorized webhook, there is a signature field with this description: This is a unique identifier for each instance of deauthorization / app uninstallation done by a user.
Is signature globally unique (i.e., the value is different for every uninstallation) or unique for a user (i.e., the value is different for every uninstallation done by the user whose user_id is included in the payload)?
