title: Removing everything but the regex result (Notepad++)
body: <p>I have such tags</p>
  
  <pre><code>&lt;span class="123"&gt;Apple&lt;/span&gt;
  &lt;span class="123"&gt;Red Banana&lt;/span&gt;
  &lt;span class="123"&gt;Yellow Car&lt;/span&gt;
  &lt;span class="123"&gt;Hello everyone&lt;/span&gt;
  </code></pre>
  
  <p>that contain different kind of text inside of them (Apple, Red Banana, etc.). The "class" is always the same – "123". 
  All these tags are among other tags and HTML elements that I don't need. What I need is to extract only the text inside the <code>&lt;span class="123"&gt;&lt;/span&gt;</code> tag.</p>
  
  <p>I already figured out a regex expression to select these elements:</p>
  
  <pre><code>&lt;span class="123"&gt;\K.+?(?=&lt;/span&gt;)
  </code></pre>
  
  <p>But now I would like to remove everything excepting what I just selected. I already tried to bookmark them and remove the "Unmarked Lines", but I am left with whole lines that I don't actually need.</p>
  
  <p>Does anyone have an idea how I can just replace everything but my selection with "nothing" ?</p>
  
  <p>Best,
  john06</p>