JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="enter"/>
    <div id="content"></div>
    <div id="link" ></div>

JavaScript

$("#enter").bind("keyup", function() {
    $("#content").html($("#enter").val());
});

$.expr[":"].containsNoCase = function(el, i, m) {
    var search = m[3];
    if (!search) return false;
    // we'll use text to find what we want...
    return eval("/" + search + "/ig").test($(el).text());
};


if (!window.Kolich) {
    Kolich = {};
}

Kolich.Selector = {};
Kolich.Selector.getSelected = function() {
    var t = '';
    if (window.getSelection) {
        t = window.getSelection();
    } else if (document.getSelection) {
        t = document.getSelection();
    } else if (document.selection) {
        t = document.selection.createRange().text;
    }
    return t;
}

$.expr[":"].containsNoCase = function(el, i, m) {
    var search = m[3];
    if (!search) return false;
    // we'll use text to find what we want...
    return eval("/" + search + "/ig").test($(el).text());
};


Kolich.Selector.mouseup = function() {
    var st = Kolich.Selector.getSelected();
    if (st != '') {
        // alert("You selected:\n" + st);
        // wrap selecetd word in a link
        $("#content:containsNoCase('" + st + "')").each(function() {
            var textwithLink = '<a href="javascript:alert(\'link-to-selected-text.htm\')">' + st + '</a>';

            $("#link").html(textwithLink);

        });
    }
}

$(document).ready(function() {
    $(document).bind("mouseup", Kolich.Selector.mouseup);
});