When trying to open a GUI-program on a SSH-Session with X11-Forwarding (both client and server have X11Forwarding activated) I get this error:
Xlib: extension "XInputExtension" missing on display ":4". Application asked to unregister timer 0x8000003 which is not registered in this thread. Fix application.
VNC to this server is working correctly.
OS: Ubuntu Server
Thanks!