JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="dlist" class="sortable">
    <li id="listItem_000002">
        <div>
            <div><a class="itemCollapse"></a>
            </div>Item 2</div>
    </li>
    <li id="listItem_000003">
        <div>
            <div><a class="itemCollapse"></a>
            </div>Item 3</div>
    </li>
    <li id="listItem_000009">
        <div>
            <div><a class="itemCollapse"></a>
            </div>Item 9</div>
    </li>
    <li id="listItem_000012">
        <div class="hiddenItem">
            <div><a class="itemCollapse"></a>
            </div>Item 12 (Hidden)</div>
    </li>
</ul>
<br>
<br>
    
<a class="count">Count</a>

CSS

.count {
    cursor:pointer;
    color:#00C;
    text-decoration:underline;
}

JavaScript

$(".count").click(function () {
    var tcount = $("#dlist").children("li").length;
    alert(tcount);
});