title: How to extract all the current video files and its address in the web page with js?
body: <pre><code> var imgs=document.images.length;
  </code></pre>
  
  <p>It can extract all the images on the web page.<br>
  How extract all the flv files whose suffix is flv such as <code>sample.flv</code> in the web page with js?Not all the flv files on my local directory but web page.<br>
  The plugin <code>Video DownloadHelper</code> in firefox can get the current mp4 file.<br>
  <a href="https://i.stack.imgur.com/NVsSl.png" rel="noreferrer"><img src="https://i.stack.imgur.com/NVsSl.png" alt="enter image description here"></a>
  Why my js code can't do the same task?</p>
  
  <pre><code>var Links = document.querySelectorAll('a[href$=".mp4"]');
  console.log(Links);
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/L8LwG.png" rel="noreferrer"><img src="https://i.stack.imgur.com/L8LwG.png" alt="enter image description here"></a></p>
  
  <p>How to extract the current video files with js such as the plugin <code>Video DownloadHelper</code> in firefox?</p>