I’ve got used to dragging stuff (Files, Website-Links, Windows, …) around to other virtual desktops by pressing Strg+Alt+Arrowkey during the drag when I was using Linux Mint with Cinnamon dektop.
On KDE this works for Files & Windows, but for Website-Links taken from Firefox the arrowkeys are instead interpreted as command to move the mousepointer (!?) and the alt modifier makes it move farther with each keypress.
This might be related to:
Website-Links taken from Chromium can be dragged to other virtual desktops without any problems.