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chrome/common/extensions/docs/templates/articles/develop_apps.html

 <h1>Before You Start</h1>
 
 <p>
 This documentation tells you how to write Chrome Apps.
 All developers, however, should know that the new APIs
 for Chrome Apps are being released as a developer preview.
 This means that they are evolving daily,
 and anything you read now might be different in the near future.
 Please keep up to date with the API reference and documentation.
 </p>
 
 <p class="caution">
 <b>Note:</b>
 If you've written packaged apps before,
-your <a href="/extensions/apps.html">legacy packaged apps</a>
+your <a href="/extensions/apps">legacy packaged apps</a>
 will still work the way they always have,
 but they won't have access to the new APIs.
 </p>
 
 <h2 id="common">Common platform</h2>
 
 <p>
 Chrome Apps and extensions share a common platform.
 They can access many of the same APIs and
 they have the same manifest and permissions format.
 If you're familiar with the
-<a href="/extensions/index.html">Chrome Extension docs</a>,
+<a href="/extensions/index">Chrome Extension docs</a>,
 then the Reference docs should seem familiar.
 Many of the reference docs are shared;
 we've filtered accessibility to docs that aren't.
 </p>
 
 <h2 id="start">Where to start</h2>
 
 <ul>
   <li>Read the
-  <a href="about_apps.html">Getting Started</a> guide.</li>
+  <a href="about_apps">Getting Started</a> guide.</li>
   <li>Follow the
-  <a href="app_codelab.html">Todo App Codelab</a>.</li>
+  <a href="app_codelab">Todo App Codelab</a>.</li>
   <li>Check out the
-  <a href="api_index.html">Chrome JavaScript APIs</a>.</li>
+  <a href="api_index">Chrome JavaScript APIs</a>.</li>
   <li>Fork any and all
   <a href="https://github.com/GoogleChrome/chrome-app-samples">chrome-app-samples</a> and make something of your own.</li>
   <li>Watch the
 <a href="https://developers.google.com/live/chrome/">Chrome Apps GDL sessions</a>.</li>
 </ul>
 
 <h2 id="help">Send feedback!</h2>
 
 <p>
 For Chrome Apps to succeed,
 we need and want your feedback.
 You can enter feedback at the
 <a href="https://groups.google.com/a/chromium.org/group/chromium-apps">chromium-apps group</a>,
 file a bug at the
 <a href="http://crbug.com/new">official issue tracker</a>,
 or press "Send Feedback" at the bottom of every doc page.
 </p>
 
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