sharing clipboard feature did not work on spice protocol

I have spice-vdagent installed on both QEMU guest and host, start systemd unit service on the host and execute spice-vdagent on the guest side.

step to reproduce:

1. make sure the spice-vdagentd systemd unit service is started
2. start the guest with necessary parameters as follow: qemu-system-x86_64 -drive file=arch-btw.qcow2,media=disk,if=virtio -m 4069 -enable-kvm -net nic,model=virtio-net-pci -net user,hostfwd=tcp::4444-:22 -vga qxl -device virtio-serial-pci -spice unix=on,addr=/tmp/vm_spice.socket,disable-ticketing=on -device virtserialport,chardev=spicechannel0,name=com.redhat.spice.0 -chardev spicevmc,id=spicechannel0,name=vdagent
3. open remmina and connect to the server uri unix:///tmp/vm_spice.socket
4. login, start Xorg session and open new terminal and type spice-vdagent
5. expected result is sharing clipboard feature should be enable, but instead it didn't work

I have tried the clipboard sharing feature directly on spicy and it works without problem:

spicy --uri 'spice+unix:///tmp/vm_spice.socket'