JSFiddle - React, Tailwind, and code Playground

HTML

<div id="right"></div>
<div id="shouldberight"></div>
<div id="shouldbewrong"></div>

JavaScript

var _regex_begins_normal = new RegExp(/\b(elé)/gi),
		_regex_begins_accented = new RegExp(/\b(élé)/gi),
    
    // elé <=> elé
    _test_right = _regex_begins_normal.exec("elé"),
    
    // élé <=> élé
		_test_should_be_right = _regex_begins_accented.exec("élé"),
    
    // élé </> zélé
    _test_should_be_wrong = _regex_begins_accented.exec("zélé");


document.getElementById("right").innerHTML = "elé match with elé => " +
	(_test_right !== null ? "yes" : "no");
  
document.getElementById("shouldberight").innerHTML = "élé match with élé => " +
	(_test_should_be_right !== null ? "yes" : "no");
  
  document.getElementById("shouldbewrong").innerHTML = "élé match with zélé => " +
	(_test_should_be_wrong !== null ? "yes" : "no");