JSFiddle - React, Tailwind, and code Playground

HTML

<input type="button" id="fullscreen" value="Fullscreen" />
<div id="container"></div>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyAtjlTdtC-oZ_MqQgsNmTTOzBkFsms4aFc&callback=initMap" async="" defer=""></script>

CSS

#container {
  width: 500px;
  height: 300px;
}

#container div.gm-style > button[title="Toggle fullscreen view"] {
	display: none;
}

JavaScript

function initMap() {
  
  var container = $('#container').get(0);
   
  var map = new google.maps.Map(container, {
    center: {lat: -39.000, lng: -60.000},
    zoom: 3,
    fullscreenControl: true
  });

  $('#fullscreen').click(function() {
  	$('#container div.gm-style button[title="Toggle fullscreen view"]').trigger('click');
  });

}