title: Splitting the string with Regex yields unexpected result
body: <p>I have the following string and regex</p>
  
  <pre><code>const message = "asdasd :+1::skin-tone-4:"
  const emojiRegex = /(:[a-zA-Z0-9-_+]+:(:skin-tone-[1-6]:)?)/g
  </code></pre>
  
  <p>When I use <code>.match(emojiRegex)</code> on <code>message</code>, I get the following result which is correct:</p>
  
  <pre><code>[":+1::skin-tone-4:"]
  </code></pre>
  
  <p>But when I try to use <code>.split(emojiRegex)</code> with the same regex I get the following result:</p>
  
  <pre><code>["asdasd ", ":+1::skin-tone-4:", ":skin-tone-4:", ""]
  </code></pre>
  
  <p>I expect this as a result: </p>
  
  <pre><code>["asdasd ", ":+1::skin-tone-4:", ""]
  </code></pre>
  
  <p>What's wrong here? How should I change my regex to have the expected result?</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>const message = "asdasd :+1::skin-tone-4:"
  
  const emojiRegex = /(:[a-zA-Z0-9-_+]+:(:skin-tone-[1-6]:)?)/g
  
  console.log(message.match(emojiRegex));
  console.log(message.split(emojiRegex));</code></pre>
  </div>
  </div>
  </p>