title: How can I switch to a tag/branch in hg?
body: <p>I followed the documentation in <a href="https://developer.mozilla.org/En/Developer_Guide/Source_Code/Mercurial" rel="noreferrer">https://developer.mozilla.org/En/Developer_Guide/Source_Code/Mercurial</a>
  and downloaded FF source with:</p>
  
  <pre><code>hg clone http://hg.mozilla.org/mozilla-central/ src
  </code></pre>
  
  <p>How can I switch to the FF3.6 'branch' or 'tag'? The documentation said</p>
  
  <pre><code>hg clone http://hg.mozilla.org/releases/mozilla-1.9.2/ 192src
  </code></pre>
  
  <p>but I don't want to clone both FF main and FF3.6 twice?</p>