title: Why is useEffect running twice?
body: <pre><code>import { useContext, useEffect, useState } from 'react';
  
  const Log =  ()  =&gt;  {
      useEffect(()  =&gt; {
          console.log('Running ...')
      },[])
  
      return(&lt;p&gt;here&lt;/p&gt;)
  
  }
  
  export default Log;
  </code></pre>
  <p>Whenever this code runs, I get
  <strong>Running...</strong> messages twice in the browser console.</p>
  <p>I think it should run once, as I have an empty second parameter in useEffect.</p>
  <p>Can anybody explain why it is getting run twice?</p>