title: Is it possible to set config settings on Firefox from a Addon
body: <p>I'm looking for a way to print from web without prompting the print dialog (<a href="https://stackoverflow.com/questions/5809102/how-to-print-from-web-without-prompting-a-print-dialog-on-windows" title="I just made this question">I just made the question</a>).</p>
  
  <p>I found <a href="http://www.bauer-power.net/2007/12/print-without-prompt-in-firefox.html" rel="nofollow noreferrer" title="This method for Firefox">This method for Firefox</a> and it seems to work, but it obviously will affect all websites. So I'm thinking of developing a Firefox Addon that makes this configuration to affect only specific websites.</p>
  
  <p>I don't know nothing about building Firefox addons, but if it's possible to change settings this way I will learn how to do it.</p>
  
  <p>So my question is.. Is it possible to set config settings on Firefox from a Addon and for specific websites?</p>
  
  <p>Thanks a lot.</p>