title: iOS 13 - UITextField with Placeholder getting app crash
body: <p>In iOS 13, I'm getting a crash when accessing the <code>UITextField</code> _placeholderLabel.textColor label key.</p>
  <p>The key used to apply placeholder text color.</p>
  <pre><code>[textfield setValue:[UIColor whiteColor] forKeyPath:@&quot;_placeholderLabel.textColor&quot;];
  </code></pre>
  <blockquote>
  <p>&quot;NSGenericException&quot; - reason: &quot;Access to UITextField's _placeholderLabel ivar is prohibited. This is an application bug&quot;</p>
  </blockquote>