Missing XInputExtension when using XForwarding over SSH

I recently had some issues whilst trying to tunnel an Xsession over to another machine (basically as I was too lazy to walk downstairs to my Mythtv box to use xxdiff to analyse 2 config files).

Using this command
ssh -X mythtv

resulted in many error messages once i ran any app that would have launched a Xdisplay:

mythtv ~ # xxdiff httpd.conf httpd.conf.old
X Error: BadDrawable (invalid Pixmap or Window parameter) 9
Major opcode: 55
Minor opcode: 0
Resource id: 0x1a6
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 2
Minor opcode: 0
Resource id: 0x1a6
Xlib: extension "XInputExtension" missing on display "localhost:10.0".
Failed to get list of devices
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 2
Minor opcode: 0
Resource id: 0x1a6
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 2
Minor opcode: 0
Resource id: 0x1a6
X Error of failed request: BadGC (invalid GC parameter)
Major opcode of failed request: 60 (X_FreeGC)
Resource id in failed request: 0x3200000
Serial number of failed request: 131
Current serial number in output stream: 133

Apparently the current version of SSH limits the X Window extensions that can be used. XInputExtension is one of these. If instead you use “-Y” it will accept ALL these X Window extensions and it works

ssh -Y mythtv

Great!

Laziness promotes education.