Focus widget not updated after drop

To reproduce with Qt Designer:

• Start designer, create a form
• Right click on Widget box, notice context menu ("Expand all") etc.
• Drag a widget onto the form
• Right click on the dropped widget.
  EXPECTED: The widget context menu appears (offering "edit tooltip", "text", etc)
  ACTUAL: The context menu of the Widget box appears again

To reproduce with the attached example:

• Right click on list items, notice that the context menu has the widget name List1, List2, respectively
• Drag an item from List1 onto List2
• Right click in List2.
  EXPECTED: Context menu has object name 'List2' (debug output says focus widget is 'list 2')
  ACTUAL: Context menu has 'List1' (debug output says focus widget is 'list 1')