JSFiddle - React, Tailwind, and code Playground

HTML

<div id="loginWindow" tabindex="-1" role="dialog" class="modal fade" aria-hidden="true">
    <div class="modal-dialog">
        <div class="model-content">
            <div class="modal-header">
                <button type="button" data-dismiss="modal" class="close">
                    <span aria-hidden="true">Ă—</span>
                    <span class="sr-only">Close</span>
                </button>
                <h4 id="loginLabel" class="modal-title">Log in</h4>
            </div>
            <div class="modal-body">
                <input id="email" type="text">
            </div>
            <div class="modal-footer">
                <p>blablabla</p>
            </div>
        </div>
    </div>
</div>
    
    <button id='loginButton'>Open</button>

JavaScript

$(document).ready( function() {

	// set focus when modal is opened
	$('#loginWindow').on('shown.bs.modal', function () {
    	$('#email').focus();
	});

	// everytime the button is pushed, open the modal, and trigger the shown.bs.modal event
	$('#loginButton').click(function () {
    	$('#loginWindow').modal({
        	show: true
    	});
	});

});