You mean drag-n-drop? Yes, nearly all Desktop Environments can do that, budgie does not allow it to happen trough panel or use alt+tab, unfortunatelly, but you can just resize the windows you want and drag-n-drop, for example:
Files(nautilus) is open, and firefox on the back maximized, I drag and drop an image/file to upload to an website.
Also other applications can do that, like gimp, inkscape, wine apps, nearly everything...
