A rich text area on a dialog box looses its content if we move the dialog box

If you put a rich text area on a dialog box and then drag the dialog to another location the content of the text area before the drag is lost. This happens because during dragging widgets are removed from the dialog box in order to speed up the dragging process. When the drag stops and the rich text area is reattached its contents are lost because currently the rich text area is based on an in-line frame which creates a new inner document each time it is (re)attached to the DOM tree.