copy/paste works with text but not with files

I'm using Qemu to have a Windows virtual machine (which is integrated to an active-directory domain). I want to copy/paste a file from my host (archlinux) to my guest (Windows 10 Business). For that, I use spice. Thus, I start qemu with the following command:

qemu-system-x86_64 -enable-kvm
  -cpu host
  -smp 4
  -drive if=pflash,format=raw,file=OVMF.fd
  -vga qxl
  -device virtio-serial-pci
  -spice port=5930,disable-ticketing=on
  -device virtserialport,chardev=spicechannel0,name=com.redhat.spice.0
  -chardev spicevmc,id=spicechannel0,name=vdagent
  -m 16G
  Windows.qcow2

(line breaks inserted for readability) Then, I use spicy to connect to it. I installed spice-guest-tools on the guest Windows virtual machine. The copy/paste works well for a text but not for a file. I use thunar as file manager on Linux. Do you know why? Also I don't want to use virt-manager.