title: How to sign a Firefox Extension
body: <p>I want to sign a Firefox extension. I have search on internet regarding signing the extension and found the URL <a href="https://developer.mozilla.org/en/docs/Signing_a_XPI" rel="nofollow noreferrer">https://developer.mozilla.org/en/docs/Signing_a_XPI</a>.
  I have gone through the instructions given in this site. But could not sign-in the extension. In my case <em>signtool</em> and <em>certutil</em> commands are not running.</p>
  <p>if anyone know the process of signing a Firefox extension then please let me know.
  Thanks.</p>