title: Greasemonkey does not recognize and can't install local scripts
body: <p>I can't install new <code>*.user.js</code> local scripts. I use Firefox 11.0, and Greasemonkey 0.9.18.</p>
  
  <p>When I open (Firefox - File - Open) a <code>.user.js</code> file on my local disk, it is not recognized as a Greasemonkey user script. </p>
  
  <p>However, if I enter a URL to a <code>.user.js</code> file, it is recognized and installed by Greasemonkey. </p>