Contact Overlay for Opportunities and Appointments
Open a contact without leaving the page you are working on. From Opportunities, click a contact name or the conversation icon; from Appointments, click a contact name. The contact opens in an overlay instead of redirecting to the full Contact Details page.
The overlay offers a Single column view, a Two column view, or Go directly to the Contact details page, and it respects your Contact Detail Page customizations. Open the full contact page from the overlay and return to your previous page when you are done.
See Open a contact overlay from Opportunities and Appointments for the details.