title: Permission denied when trying to open Firefox to run Selenium tests via Django's manage.py
body: <p>I'm running on Ubuntu 16.04.</p>
  
  <p>I've been dealing with this issue for a while now, and I have not been able to find a solution on my own.  When I run python3 manage.py test, my tests are to open a Firefox browser via Selenium and execute some functional tests.  I get the same error message on every test I try to run;</p>
  
  <pre><code>selenium.common.exceptions.WebDriverException: Message: Failed to start browser /home/spa/Desktop/firefox: permission denied
  </code></pre>
  
  <p>I have tried to do chmod a+rwx on the firefox folder, but I still get the same error.  Attempting to sudo python3 manage.py test results in the same issue.  Any help would be appreciated.</p>