[otrs] upgrade from 2.3.4 to 2.4.3 missing features :(

Hy all, i've recently upgraded in a vm test our otrs system to 2.4.3, but as i can see the very powerful dashboard, it seems i'm missing some of the new features like the new ticket list view, bulk action .... ? any clues why and how to gain access to all the cool new features ? Rachid