title: RegEx: Negated lookahead a back reference many times
body: <p>How do we lookahead until there is no back reference of a character in RegEx?</p>
  
  <p>Given:</p>
  
  <blockquote>
    <p>We are looking for phrases within quotes and it can be multiline "check we have a return here
     but this line is still part of previous one 'a' string".</p>
    
    <p>It breaks once we have another 'testing with single quotes "surrounding" double quotes';</p>
  </blockquote>
  
  <p>How do we look for double quotes and single quotes once they close themselves?</p>
  
  <p>I tried this pattern, but it's not working:</p>
  
  <pre><code>/(['"])[^$1]+\1/g
  </code></pre>
  
  <p><a href="https://regex101.com/r/B43eci/4" rel="nofollow noreferrer">Look here</a></p>