unfortunately not.Is there any possibility to create a keyboard shortcut to toggle the floating window for the focus tool in v.5 ?
Workarounds:
Try the second viewer (menu "window"-> viewer) ... I think for your particular purposes it will work just as the focus tool. You can assign a shortcut to the second viewer.
Or mabye you create the focus tool as floating window and collapse/expand it when needed... you can place it on the top of the interface so it doesn't hurt when collapsed.