Remove .html extension from links

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

 <h1>Background Pages</h1>
 
 
 <p id="eventPageWarning" class="warning">
   <em>Caution:</em> Consider using event pages instead.
-  <a href="event_pages.html">Learn more</a>.
+  <a href="event_pages">Learn more</a>.
 </p>
 
 <p>
 A common need for extensions is to have
 a single long-running script to manage some task or state.
 Background pages to the rescue.
 </p>
 
 <p>
-As the <a href="overview.html#arch">architecture overview</a> explains,
+As the <a href="overview#arch">architecture overview</a> explains,
 the background page is an HTML page that runs in the extension process.
 It exists for the lifetime of your extension,
 and only one instance of it at a time is active. (Exception: if your
-extension uses <a href="manifest/incognito.html">incognito</a>
+extension uses <a href="manifest/incognito">incognito</a>
 "split" mode, a second instance is created for incognito windows.)
 </p>
 
 <p>
 In a typical extension with a background page,
 the UI &mdash;
 for example, the browser action or page action
 and any options page &mdash;
 is implemented by dumb views.
 When the view needs some state,
 it requests the state from the background page.
 When the background page notices a state change,
 the background page tells the views to update.
 </p>
 
 <h2 id="manifest">Manifest</h2>
 
 <p>
 Register your background page in the
-<a href="manifest.html">extension manifest</a>.
+<a href="manifest">extension manifest</a>.
 In the common case, a background page
 does not require any HTML markup.
 These kind of background pages can be
 implemented using JavaScript files alone,
 like this:
 </p>
 
 <pre data-filename="manifest.json">
 {
   "name": "My extension",
@@ skipping 25 matching lines @@
   <b>"background": {
     "page": "background.html"
   }</b>,
   ...
 }</pre>
 
 <p>
 If you need the browser to start up early&mdash;so
 you can display notifications, for example&mdash;then
 you might also want to specify the
-<a href="declare_permissions.html#background">"background" permission</a>.
+<a href="declare_permissions#background">"background" permission</a>.
 </p>
 
 
 <h2 id="details">Details</h2>
 
 <p>
 You can communicate between your various pages using direct script calls,
 similar to how frames can communicate.
 The $(ref:extension.getViews) method
 returns a list of window objects
@@ skipping 57 matching lines @@
   &lt;body>
     &lt;p>
     Image here:
     &lt;/p>
 
     &lt;img id="target" src="white.png" width="640" height="480">
 
   &lt;/body>
 &lt;/html>
 </pre>