JSFiddle - React, Tailwind, and code Playground

HTML

<table>
      <tr><td>A</td></tr>
      <tr id="trb"><td>B</td></tr>
      <tr><td>C</td></tr>
    </table>
    <p><span id="trcount">?</span> rows are visible.</p>

    <p>Using paragraphs:</p>
    <p class="item">A</p>
    <p class="item" id="pb">B</p>
    <p class="item">C</p>

    <p><span id="pcount">?</span> paragraphs are visible.</p>

JavaScript

$(document).ready(function () { 
               $('#trb').hide();
               $('#trcount').html($('tr:visible').length);
               $('#pb').hide();
               $('#pcount').html($('p.item:visible').length);
});