title: Regex - Delete all lines which don't contain a string? - Sublime Text
body: <p>I am looking for a regular expression that can help me delete all lines in sublime text which don't contain .</p>
  
  <p>For example:</p>
  
  <p>I have a text file with domains:</p>
  
  <p><code>abc.com
  def.com
  ghi.com
  com
  jkl.com
  com</code></p>
  
  <p>I would like to use a regular expression to remove all lines not containing .
  So the result should be like:</p>
  
  <p><code>abc.com
  def.com
  ghi.com
  jkl.com</code></p>
  
  <p>Thx in advance for your help! :)</p>