title: FISH error upon startup to access a file that does exist
body: <p>On an Ubuntu 14.04, I have started to receive the following warning (or error) each time I start a new session in terminal :</p>
  
  <pre><code>Unable to make or open a FIFO for universal variables with path '/run/user/0/fishd.12c79b706e7a.notifier': Permission denied
  </code></pre>
  
  <p>When I try to look into this file, the file does not exist at all. </p>