A notification is immediately sent to the impersonated user (in-platform and, if your user’s email is configured in the platform, via email) to inform them that you accessed the platform on their behalf.
Since the notification is sent to the impersonated users while you are logged in as that user, remember not to open it, so that when the user logs into his or her account, they will see the unread notification. If you open the notification, it won’t be deleted, but the user may not notice it when logging into their platform, since the red dot won’t be shown over the bell icon indicating that there are unread notifications.
When you switch back to your account, the user you impersonated receives another notification informing them that you logged out from their account.