Zoomed-out Drag & Drop view

[eessex]

cc @halleyjohnson

Halley noted that it can sometimes be hard to move sections down the page when it requires lots of scrolling, and often zooms the page out so she can see the whole layout.

We could add a pop-up modal for drag and drop, that shows each section at a glance in mini -- allowing all the sections to be visible without scrolling.