title: How can I fix `Using UNSAFE_componentWillMount in strict mode is not recommended and may indicate bugs in your code.`?
body: <p>I'm using redux forms in react project and this is the app component which has redux forms intialized :</p>
  
  <pre><code>import { Field, reduxForm } from 'redux-form';
  
  const onSubmit = (values) =&gt; {
      alert(JSON.stringify(values));
  };
  function App(props) {
      return (
          &lt;div className="App"&gt;
              &lt;form onSubmit={props.handleSubmit}&gt;
                  &lt;div&gt;
                      &lt;label htmlFor="firstName"&gt;First Name&lt;/label&gt;
                      &lt;Field name="firstName" component="input" type="text" /&gt;
                  &lt;/div&gt;
                  &lt;div&gt;
                      &lt;label htmlFor="lastName"&gt;Last Name&lt;/label&gt;
                      &lt;Field name="lastName" component="input" type="text" /&gt;
                  &lt;/div&gt;
                  &lt;div&gt;
                      &lt;label htmlFor="email"&gt;Email&lt;/label&gt;
                      &lt;Field name="email" component="input" type="email" /&gt;
                  &lt;/div&gt;
                  &lt;button type="submit"&gt;Submit&lt;/button&gt;
              &lt;/form&gt;
              {props.number}
              &lt;button onClick={() =&gt; props.callAction()} /&gt;
          &lt;/div&gt;
      );
  }
  
  
  App = reduxForm({
      form: 'contact',
      onSubmit
  })(App);
  
  </code></pre>
  
  <p>But I get this error in the console which is coming from react strict mode :</p>
  
  <pre><code> Using UNSAFE_componentWillReceiveProps in strict mode is not recommended and may indicate bugs in your code.
  * Move data fetching code or side effects to componentDidUpdate.
  * If you're updating state whenever props change, refactor your code to use memoization techniques or move it to static getDerivedStateFromProps. Learn more at:state
  
  Please update the following components: Field, Form(App)
  </code></pre>
  
  <p>How can I fix this error ?</p>