title: Negative Lookbehind in firefox
body: <p>I just learned the hard way that negative lookbehinds are not supported in firefox. Just deployed to production and all seemed fine. Once our firefox users started hitting it, they got nothing.</p>
  
  <p>Is there a pollyfill or some alternative to this regex?</p>
  
  <pre><code>"Item 1, Item2^, Item2a, Item3".split(/(?&lt;!\^),/)
  </code></pre>
  
  <p>I am trying to split a string into arrays on a commas but not on <code>^,</code></p>
  
  <p>"Item 1, Item2^, Item2a, Item3"</p>
  
  <p>Should end up as </p>
  
  <pre><code>[
  "Item 1",
  "Item2^, Item2a",
  "Item3"
  ]
  </code></pre>