simply log onto the synth . . .
type raspi-config
Tab to ok, select with space bar
Scroll down to 5 Interfacing Options.
Enter to select.
Select P3 VNC… Select
So that’s the synth end done.
Download the realvnc client for your operating system…
Enter the zynthian.local address ( from web conf or Netwrk info on GUI)
and provide login details ( root and you have changed the default password when you renamed the synth haven’t you?)
Escape key works like back.