Make highlight list scrollable
The highlight list can not be scrolled independent of an open document. This makes searching for existing highlights difficult, considerably with multiple users and long highlight lists. Being able to scroll the list of highlights separately in the left viewport would be great. This would also help when working with the highlights. If the highlight list is longer than the screen and you scroll down to a highlight and click it, entries are shown in the not visible area of the right viewport. This is considerably difficult if the hierarchy of highlights is used, since the context of a highlight is not longer visible after scrolling up to the text.