JSFiddle - React, Tailwind, and code Playground

HTML

<b class="xyzxterms" style="cursor: default; ">bryant keil bio</b>

JavaScript

var element = document.getElementsByTagName('b')[0];

var new_element = document.createElement('h1'),
    old_attributes = element.attributes,
    new_attributes = new_element.attributes,
    child = element.firstChild;

for (var i = 0, len = old_attributes.length; i < len; i++) {
    new_attributes.setNamedItem(old_attributes.item(i).cloneNode());
}

do {
    new_element.appendChild(child);
} while (child = child.nextSibling);

element.parentNode.replaceChild(new_element, element);