X forwarding firefox in OSX yosemite

 hoolio@macbook:~$ ssh -Y server  
 Warning: No xauth data; using fake authentication data for X11 forwarding.  
 Last login: Thu May 14 11:03:26 2015 from xxx  
 $ firefox &;  
 [1] 18949  
 $ connect localhost port 6000: Connection refused  
 connect localhost port 6000: Connection refused  
 connect localhost port 6000: Connection refused  
 Error: cannot open display: localhost:0.1  
 ^C  
 [1]+ Exit 1         firefox  

Apparently X is no longer a part of OSX, and you have to install xquartz to get x forwarding again.

 hoolio@macbook:~$ ssh -Y server  
 /opt/X11/bin/xauth: file /Users/hoolio/.Xauthority does not exist  
                                  Last login: Thu May 14 11:39:05 2015 from xxx
 $ firefox &  
 [1] 20620  
console.error:  
  [CustomizableUI]  
  Custom widget with id loop-button does not return a valid node  
 console.error:  
  [CustomizableUI]  
  Custom widget with id loop-button does not return a valid node  
 SystemMessageCache: init  

and up pops a firefox window, hooray :)  now it's just working out why its .. so.. slooow....

EDIT: i discovered it's to do with the ssh encryption type.  try this;

 hoolio@macbook:~$ ssh -Y -C -o CompressionLevel=9 -c arcfour,blowfish-cbc server firefox -no-remote  

and DON'T do it over wifi; the double encryption plus inherent X latency make it terribly slow.