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 <p>This is our documentation section explaining how to build extensions for the Chromium-based <a href="http://www.opera.com/computer">Opera browser</a> for computers. Note: as a developer, you can also grab an <a href="http://www.opera.com/developer">Opera Developer</a> build, which has the latest new stuff.</p>
 <p>With Opera switching <a href="http://my.opera.com/ODIN/blog/300-million-users-and-move-to-webkit">from Presto to Chromium</a> in 2013, our extensions infrastructure has also gotten a major overhaul: from <a href="http://www.opera.com/developer/next/">Opera 15</a> onward, <a href="https://github.com/operasoftware/operaextensions.js/tree/master/docs">Opera 11 &amp; 12’s extension format</a> is no longer supported, and instead, <strong>we’ve switched to Chromium’s extension model</strong>. At this point, <a href="apis.html">Opera supports most Chromium extension APIs</a>, as well as its own APIs to make extensions for the <a href="speeddial.html">Speed Dial</a> and the <a href="sidebarAction.html">Sidebar of the browser</a> .</p>
 <p>If you have created a Chromium extension before, be sure to try it out in Opera, and if it works fine, upload it to our <a href="https://addons.opera.com/extensions/">extensions catalog</a>.</p>
 <p><a href="tut_getting_started.html" class="btn btn-primary btn-large">Let’s get started »</a></p>
 <p>And if you have questions, <a href="contact.html">contact us</a>.</p>
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