JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
</head>
<body>
  <p>search me</p><b> I could be the answer</b>
    <p>search me</p><b> I could be the answer</b>
  <div>
      <button class="btn-display" data-display="inline">Inline</button>
      <button class="btn-display" data-display="block">Block</button>
      <button class="btn-display" data-display="inline-block">Inline-Block</button>
  </div>
  <div>
      <textarea id="res"></textarea>
  </div>
</body>
</html>

CSS

#res {
    width: 400px;
    height: 300px;
    resize: none;
}
div {
    margin: 7px 0;
}

JavaScript

function _find(str) {
    var div = document.createElement('div');
    div.innerHTML = document.body.innerHTML;
    var elements = div.getElementsByTagName('*');
    for(var i = elements.length; 0 > i--;) {
        elements[i].style.display = 'inline';
    }
    return (div.innerText || div.textContent).indexOf(str) > -1;
}

function containsStr(str) {
    return (document.body.innerText || document.body.textContent).indexOf(str) > -1;
}

function containsStrEx(str) {
    return (document.body.innerText || document.body.textContent)
        .replace("\n", "")
        .indexOf(str) > -1;
}

function containsStr$(str) {
    return $('body:contains("'+str+'")').length > 0;
}

function test(str) {
    printLn('_find(str): ', _find(str));
    printLn('containsStr(str): ', containsStr(str));
    printLn('containsStrEx(str): ', containsStrEx(str));
    printLn('window.find(str): ', window.find(str));
    printLn('jQuery :contains selector: ', containsStr$(str));
    printLn(SEPARATOR);
}

var str = "me I could be",
    console$ = $('#res'),
    SEPARATOR = new Array(32).join('-');

function printLn(s) {
    print(Array.prototype.join.call(arguments, ''), "\n");
}

function print(s) {
    console$[0].value += Array.prototype.join.call(arguments, '');
    console$.scrollTop(console$[0].scrollHeight - console$.height());
}

$(document).on('click', '.btn-display', function() {
    $('p').css('display', $(this).data('display'));
    test(str);
});