It looks like drag & drop is not at the moment working.
It would be helpful to be able to drag and drop widget/blocks between one widget area and another.
Example from the old Widget Screen:

Drag and drop between widget areas is already available. The issue now is that the areas need to be opened.
Drag and drop between widget areas is already available. The issue now is that the areas need to be opened.
Do you mean, because the second widget area isn't opened we can't drag and drop form one to the other ?
What I noticed
I believe we can go ahead and close this issue. As the PR for dragging & dropping widgets between widget areas have been merged.