Did 'Contact' logic change significantly in latest version?

If I upgrade to the latest version of eM Client (from 4.0.15145.0) will the ‘CONTACT’ logic work the same? I now have contacts in separate folders by state and support type. Don’t want to loose this great feature!! (Google gmail cannot do what you do.)

The only change made to contact is that they do not display in the Sidebar now. Everything else should be the same.