JSFiddle - React, Tailwind, and code Playground

HTML

<b>
    <input type="checkbox" value="" />
    I need replaced
</b><br />
<b>
    <input type="checkbox" value="" />
    I need replaced
</b><br />
<b>
    <input type="checkbox" value="" />
    I need replaced
</b><br />
<b>
    <input type="checkbox" value="" />
    I need replaced
</b><br />
<b>
    <input type="checkbox" value="" />
    I need replaced
</b>

JavaScript

var highlightSomeText = function(needle, node){
    node = node || document.body; // initialize the first node, start at the body

    if(node.nodeName == 'SCRIPT') return; // don't mess with script tags 

    if(node.nodeType == 3){ // if node type is text, search for our needle
        var parts = node.nodeValue.split(needle); // split text by our needle
        if(parts.length > 1){ // if we found our needle
            var parent = node.parentNode
            for(var i = 0, l = parts.length; i < l;){
                var newText = document.createTextNode(parts[i++]); // create a new text node, increment i
                parent.insertBefore(newText, node);
                if(i != l){ // if we're not on the last part, insert a new span element for our highlighted text
                    var newSpan = document.createElement('span');
                    newSpan.className = 'textSearchFound';
                    newSpan.style.color = '#0095DA';
                    newSpan.innerHTML = needle;
                    parent.insertBefore(newSpan, node);
                }
            }
            parent.removeChild(node); // delete the original text node
        }
    }

    for(var i = node.childNodes.length; i--;) // loop through all child nodes
        highlightSomeText(needle, node.childNodes[i]);
};

highlightSomeText('I need');