I have a RadDocking with tabbed documenthost.
If I have only one tab in DocumentHost and I dragged it, the content of the floating window is empty, when I dock again the tab the content is correctly restored.
If I have many tabs in DocumentHost and I dragged one, the content is correctly displayed.
I attached two images that explain the two cases
With 2 or more tabs (correct):
With only one tab (empty) (the content of the second panel should be the same of first image)
Furthermore, in both cases the header is missing.