title: Can't run "ssh -X" on MacOS Sierra
body: <p>I just upgraded to MacOS Sierra, and I realized that I can't seem to run the "ssh -X" command in the Terminal anymore. It used to launch xterm windows, but now it's like I didn't even put the -X option anymore. It was working absolutely fine right before I updated. Other than going from OS X Yosemite to MacOS Sierra, I didn't change anything else in the setup.</p>
  
  <p>EDIT:</p>
  
  <p>As suggested, this is what I found in the debug logs that might be causing this problem.</p>
  
  <pre><code>debug1: No xauth program.
  Warning: untrusted X11 forwarding setup failed: xauth key data not generated
  </code></pre>