4.25 The X11 panel
The X11 panel allows you to configure forwarding of X11 over an SSH connection.
If your server lets you run X Window System graphical applications, X11 forwarding allows you to securely give those applications access to a local X display on your PC.
To enable X11 forwarding, check the ‘Enable X11 forwarding’ box. If your X display is somewhere unusual, you will need to enter its location in the ‘X display location’ box; if this is left blank, PuTTY will try to find a sensible default in the environment, or use the primary local display (:0) if that fails.
See section 3.4 for more information about X11 forwarding.