While i've discovered the Explorer is using the new GXT release, I looked for new examples.

Never had seen the widgetrenderergrid before, so i suppose it is new.

It has a bug when (in FF3) the last item of the list is selected, and you delete some items. When the list is at top, the scrollbar will resize. When the list is at the bottom, the scrollbar won't resize and the items still are deleted. This results in a empty grid...