title: X11 forwarding fails every 20-30 minutes
body: <p>I have XQuartz 2.7.9 installed on OS X 10.11.5 and I'm able to successfully ssh with X11 forwarding to Linux machines. At first, I can open X11 windows without a problem. However, after about 20-30 minutes I cannot open any additional X11 windows. The X11 windows I already have open are fine.</p>
  
  <p>With one Linux machine I get the error: "Fatal IO error: client killed". And on another Linux machine I get the error: "Cannot connect to X server".</p>
  
  <p>I've tried messing with the value of ConnectTimeout in /etc/ssh/ssh_config, thinking that this might help, but it didn't. As of now, what I'm doing is exiting the current ssh session and then re-sshing. This gets real annoying, real quick.</p>