Suppose I have two maximized konsole windows and I want to move a tab from one to the other. At present I have to unmaximize both windows and then drag the tab. It would be more convenient if I could start dragging in one (maximized) window, drag the tab over a taskbar entry of the other window, the window got raised / activated and I could finish dragging in the target window. Some applications already behave like that when something is being dragged onto their taskbar entry.