To open a message, go to your mailbox and click the corresponding row of the message. The message header displays the subject and the date of delivery, the portrait, and email address of the sender, as well as the email addresses of recipients.
The sender's portrait is extracted either from the data specified in the sender's email settings (see Sender's portrait in Yandex.Mail) or from the sender's profile in a social network. If you want to disable portraits from being displayed:
You can switch between the previous and next messages in your mailbox using the panels under the reply form.
You can also switch between all messages using the navigation panel in the upper right portion of the page: