The latest versions of the application Mail for Mac OS changed the presentation of the message lists. The email preview is displayed on the right, taking into account the wide screens of all iMacs and Macbooks in recent years. This guide shows how return to the classic presentation, that is, a list of messages without preview.
Change the preview of messages in Mail
1. In the app Mail, go to the menu Mail, Preferences.
2. Go to the tab Presentation.
3. Check the line ” Use the classic presentation »To return to a standard display.
4. Close the preferences window, the option is automatically saved and the presentation changes immediately. The email preview is below (before, it was on the right), just move down the list / preview separator bar to have only the list of messages: