JSFiddle - React, Tailwind, and code Playground
HTML
<div id="header">
Sometitle<div>
<div>
aa
</div>
<div>
bb
</div>
</div>
</div>
JavaScript
headerClone = $("#header").clone();
$(headerClone).find('div').remove();
var currentText = $(headerClone).html().replace(/(\r\n|\n|\r|\t)/gm,"");
newHtml = $("#header").html().replace(currentText,"Gotcha");
$("#header").html(newHtml);