title: Why does Angular build create files with 'es5' and 'es2015' but not 'es6' (or no suffix at all)?
body: <p>I recently downloaded the <code>Angular CLI</code> (@angular/cli 9.0.1). I then proceeded to create a new application so that I could create a new Angular Element, package it up, and use it in another application.</p>
  
  <p>After following a few blogs, the final step of every blog I came across all talk about creating a single JS file from the generated files dropped under the dist/ folder. For example: <a href="https://blog.bitsrc.io/using-angular-elements-why-and-how-part-1-35f7fd4f0457" rel="noreferrer">https://blog.bitsrc.io/using-angular-elements-why-and-how-part-1-35f7fd4f0457</a></p>
  
  <blockquote>
    <p>Then using the cat command, we are concatenating the <strong>runtime.js</strong>,
    <strong>polyfills.js</strong>, <strong>scripts.js</strong>, and <strong>main.js</strong> files from the dist/angular-app
    folder into a angularapp.js file inside the preview folder.</p>
  </blockquote>
  
  <p>Running <code>ng build angular-app --prod --output-hashing=none</code> instead seems to produce files named:</p>
  
  <ul>
  <li>main-es5.js</li>
  <li>main-es2015.js</li>
  <li>polyfills-es5.js</li>
  <li>polyfills-es2015.js</li>
  <li>runtime-es5.js</li>
  <li>runtime-es2015.js</li>
  </ul>
  
  <p>I scoured every single file that had the terms <strong>es5</strong> and <strong>es2015</strong> and changed it to <strong>es6</strong>, but it still produced the same <strong>es5</strong> and <strong>es2015</strong> file names. What am I doing wrong here?</p>