Display for VM destop
into the REAL desktop machine: install virt-viewer
into Proxmox ⇒ settings of the VM ⇒ Hardware ⇒ Display, select “SPICE”
Start the VM ⇒ Console ⇒ SPICE and open the file with the “Distant viewer”
Mor infos: https://pve.proxmox.com/wiki/SPICE