SUMMARY If a dragged file is not on the same virtual desktop, there are a few ways to drag it to a window at a different virtual desktop: 1) Add a desktop effect to show all opened windows and make it activate in a corner/border. Then the item can be dragged there with the mouse and dropped within the effect on a window. This however is not very accurate as only a general window can be chosen but not special region of it. 2) It is also possible to drag a file and while holding the mouse button to change the virtual desktop with keyboard shortcuts. This requires some flexibility in one's hand and fingers though. _Finally there's another possibility, which is this report about:_ 3) Activate the switching when reaching the border of the desktop. This has currently the drawback that it only works for drag'n'drop if it is set to "always". I think it makes sense to combine it with the option "Only when moving windows".
Makes sense. macOS implements this and it's quite nice IMO.