JSFiddle - React, Tailwind, and code Playground

HTML

<div class="blueDiv toBeFaddedIn"></div>
<div class="blueDiv toBeFaddedIn"></div>
<div class="blueDiv toBeFaddedIn"></div>
<div class="blueDiv toBeFaddedIn"></div>
<div class="blueDiv toBeFaddedIn"></div>

CSS

.blueDiv {
    background-color: blue;
    height:50px;
    width: 50px;
    display: none;
    
}

JavaScript

function fadeThenNext(element){
        element.fadeIn("fast", function() {
            element=element.next(".toBeFaddedIn");
            if (element.length) fadeThenNext(element);
        });
}
fadeThenNext($(".toBeFaddedIn").first());