JSFiddle - React, Tailwind, and code Playground

HTML

<table>
  <tr><td>[email protected]</td></tr>
  <tr><td>[email protected]</td></tr>
  <tr><td>[email protected]</td></tr>
</table>

JavaScript

var emails = [];
    var table = document.getElementsByTagName('table')[0];
    var rows = table.rows;
    for (var i = 0; i < rows.length; i++) {
        var rowText = rows[i].firstChild.textContent;
        if (~rowText .indexOf('@')) { // If the content of the row contains a '@' character
            emails[emails.length] = rowText;
        }
    }
    console.log(emails);
    document.write(emails);