Web editors 'Pages navigator' section hides item "under the fold"

Currently, the Pages navigator / List section of the Layers tab doesn’t show or hint that there might be more pages hidden under the fold:

Making it difficult for people to discover they have to either drag (the bottom edge of the list section to the bottom) to reveal the additional hidden items. The scrollbar is also hidden when inactive / not hovering over the section (under chrome) making it unclear the section is also scrollable.