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

 <h1>Disabled Web Features</h1>
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 <p>
 Though Chrome Apps use the web platform,
 some web features have been disabled
 or else are used in a different way.
 Mainly this is to avoid security issues and
 to improve programming practices.
 Below is a summary of the disabled features
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     <td><code>document.open</code></td>
     <td>N/A.</td>
   </tr>
   <tr>
     <td><code>document.write</code></td>
     <td>Use document.createElement.</td>
   </tr>
   <tr>
     <td>External resources</td>
     <td>Use the <code>webview</code> tag for iframes.
-      See <a href="app_external.html">Embed Content</a>
-      and <a href="webview_tag.html">Webview Tag API</a>.
+      See <a href="app_external">Embed Content</a>
+      and <a href="webview_tag">Webview Tag API</a>.
       Video and audio are allowed to have non-local URLs.</td>
   </tr>
   <tr>
     <td>Flash</td>
     <td>Use HTML5 Platform.</td>
   </tr>
   <tr>
     <td>Form submission</td>
     <td>Use JavaScript to process form content
       (listen for submit event, process data locally first
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   <tr>
     <td>User Text selection</td>
     <td>By default,
         users can no longer select text like they can on a web page.
         To make areas of the app's text selectable,
         apply the CSS style, <code>-webkit-user-select: text;</code>.</td>
   </tr>
   <tr>
     <td>webSql</td>
     <td>Use IndexedDB or
-      <a href="app_storage.html">Filesystem API</a>.</td>
+      <a href="app_storage">Filesystem API</a>.</td>
   </tr>
 </table>
 
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