title: The Chrome extension popup is not working, click events are not handled
body: <p>I have created a JavaScript variable and when I click on the button it should increment by 1, but its not happening.</p>
  
  <p>Here's <code>manifest.json</code>.</p>
  
  <pre><code>{
    "name":"Facebook",
    "version":"1.0",
    "description":"My Facebook Profile",
    "manifest_version":2,
    "browser_action":{
      "default_icon":"google-plus-red-128.png",
      "default_popup":"hello.html"
    }
  }
  </code></pre>
  
  <p>Here is the code for the html page </p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
  &lt;head&gt;
  &lt;script&gt;
  var a=0;
  function count()
  {
    a++;
    document.getElementById("demo").innerHTML=a;
    return a;
  }
  &lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;p id="demo"&gt;=a&lt;/p&gt;
  &lt;button type="button" onclick="count()"&gt;Count&lt;/button&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>I want the extension to show me the value of a and increment it by one each time I click on the extension or the button</p>
  
  <p><img src="https://i.stack.imgur.com/G0dMA.png" alt="picture of the extension"></p>