title: ReactJS Environment variables are undefined on development
body: <p>I cannot use my environment variables on my development (localhost) with ReactJS.</p>
  <p>I made sure of following:</p>
  <ol>
  <li>My .env file is in the root directory</li>
  <li>My env variable has a prefix of <code>REACT_APP_*</code> and the usage is <code>process.env.REACT_APP_*</code></li>
  <li>My env variable does not contain <code>''</code> and contains <code>=</code> as well as it does not contain <code>;</code> or <code>,</code> so the definition is <code>REACT_APP_SOMETHING = something</code></li>
  <li>Restarted server multiple times by ctrl + c and yarn start</li>
  <li>I checked (and copied &amp; pasted) all the variable names to make sure and avoid misspelling</li>
  </ol>
  <p>Even after all of this if I try to use them (for example with <code>console.log(process.env.REACT_APP_SOMETHING)</code>) it prints only undefined. Is there anything that has to be done in <code>package.json</code> scripts? The definition is only:</p>
  <pre><code>&quot;scripts&quot;: {
      &quot;start&quot;: &quot;react-scripts start&quot;,
      &quot;build&quot;: &quot;react-scripts build&quot;,
      &quot;test&quot;: &quot;react-scripts test&quot;,
      &quot;eject&quot;: &quot;react-scripts eject&quot;
    },
  </code></pre>
  <p>I used create-react-app to initialize my project.</p>
  <p>Printing for example <code>console.log(process.env.NODE_ENV)</code> works fine. I tried even creating .env.development file with no luck.</p>