JSFiddle - React, Tailwind, and code Playground

HTML

<div class='nochange'>a desired output for range (2,14) another desired output for range (2,14)</div>
<div class='jquery'>a desired output for range (2,14) another desired output for range (2,14)</div>
<div class='nativejs'>a desired output for range (2,14) another desired output for range (2,14)</div>

JavaScript

/* jQuery */
$('.jquery').html(function (index, oldHTML) {
    return oldHTML.replace(oldHTML.substr(2, 14), '<code style="margin: 0.1em;background-color: #EFE7DF;">' + oldHTML.substr(2, 14) + '</code>');
});

/* Native Javasript */
var elements = document.getElementsByClassName("nativejs");
for (var i in elements) {
    var element = elements[i];
    element.innerHTML = element.innerHTML.replace(element.innerHTML.substr(2, 14), '<code style="margin: 0.1em;background-color: #EFE7DF;">' + element.innerHTML.substr(2, 14) + '</code>');
}