title: How to use locale in material ui datepicker (MuiPickersUtilsProvider)?
body: <p>I am using <a href="https://github.com/iamkun/dayjs" rel="noreferrer">dayjs</a> to convert my times in js.</p>
  
  <p>According to the page on <a href="https://material-ui-pickers.dev/localization/calendar-systems" rel="noreferrer">material-ui-pickers regarding localization</a> it gives an example on how to localize the date picker.</p>
  
  <p>But no luck trying that example:</p>
  
  <pre><code>import React from "react";
  import ReactDOM from "react-dom";
  import {
    KeyboardDatePicker,
    MuiPickersUtilsProvider
  } from "@material-ui/pickers";
  // import dayjs from 'dayjs';
  import "dayjs/locale/nl";
  import DayjsUtils from "@date-io/dayjs";
  
  import "./styles.css";
  
  function App() {
    return (
      &lt;div className="App"&gt;
        &lt;MuiPickersUtilsProvider utils={DayjsUtils} locale="nl"&gt;
          &lt;KeyboardDatePicker /&gt;
        &lt;/MuiPickersUtilsProvider&gt;
      &lt;/div&gt;
    );
  }
  
  const rootElement = document.getElementById("root");
  ReactDOM.render(&lt;App /&gt;, rootElement);
  </code></pre>
  
  <p>Working example: <a href="https://codesandbox.io/s/clever-field-2gzmf" rel="noreferrer">https://codesandbox.io/s/clever-field-2gzmf</a></p>
  
  <p>I also tried some methods as described in the generic <a href="https://github.com/iamkun/dayjs#i18n" rel="noreferrer">dayjs documentation I18n</a>, which also does not seem to work. </p>
  
  <p>Does someone have an idea what's doing wrong? I feel it's something trivial.</p>
  
  <hr>
  
  <p>After some further investigation it seems that either my implementation of dayjs is wrong, or there is a bug. Because moment JS is working, as this live example shows: <a href="https://codesandbox.io/s/young-snow-ejinu" rel="noreferrer">https://codesandbox.io/s/young-snow-ejinu</a></p>
  
  <p>But, on the other hand, the demo page of the Datepicker is also using moment and that isn't working: <a href="https://material-ui-pickers.dev/localization/moment" rel="noreferrer">https://material-ui-pickers.dev/localization/moment</a></p>