Although you can't do it with ssh or with tightvnc, RealVNC have released an alpha version that gets around this. On your Pi do:
curl -OL https://github.com/RealVNC/raspi-preview/releases/download/188.8.131.5206/VNC-Server-5.3.1-raspi-alpha1.deb
sudo dpkg -i VNC-Server-5.3.1-raspi-alpha1.deb
To run VNC Server in Service Mode:
sudo systemctl start vncserver-x11-serviced.service
To have VNC Server start automatically when you power the Pi on:
sudo systemctl enable vncserver-x11-serviced.service
Create a file in /home/pi/.vnc/config containing
-geometry 1280x720 to set the window size.
Download the viewer for Windows https://www.realvnc.com/download/viewer/
To make the most of VNC Server's hardware acceleration, configure VNC Viewer in the following way:
- Run VNC Viewer and connect to the Raspberry Pi.
- On the VNC Viewer toolbar, click the Options button. Click Advanced..., then the Expert tab.
- Set PreferredEncoding to JPEG
- AutoSelect to False
- ColorLevel to Full.