it would be pretty useful if the filed's sidebar widget has a fixed CSS position, especially when you need to add a field on a very large form.
for example, if you are in the bottom of your very large form, and you need to add a new field, you must go at the top of the page select the new field, and then scroll down at the bottom to see the change. i'll be easier if the sidebar widget would has a fixed position respect the window, so the widget will be always be present at the sidebar.
