[fix] id duplication

searx/templates/about.html

@@ -37,7 +37,7 @@
 <p>It's ok if you don't trust us regarding the logs, <a href="https://github.com/asciimoo/searx">take the code</a> and run it yourself! decentralize!</p>
 <h3>How to add to firefox?</h3>
 <p><a href="#" onclick="window.external.AddSearchProvider(window.location.protocol + '//' + window.location.host + '/opensearch.xml')">Install</a> searx as a search engine on any version of Firefox! (javascript required)</p>
-<h2 id="faq">Developer FAQ</h2>
+<h2 id="dev_faq">Developer FAQ</h2>
 <h3>New engines?</h3>
 <p><ul>
     <li>Edit your engines.cfg, see <a href="https://raw.github.com/asciimoo/searx/master/engines.cfg_sample">sample config</a></li>