Navigator
What was once called "Blattübersicht" should be rewritten to become the main navigator. It should present thumbnails, checkboxes for topics to browse and represent a hybrid linear and serial list of topics in a notebook. the prev and next buttons should act based on selected topics - that will enable users to flip through a notebook from topic to topic - including non linear parts displayed in a correct (readable) order.
Edited by Mathias Goebel