JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/ui-lightness/jquery-ui.css">
<div id="images_wrapper">
    
    <img src = "http://dummyimage.com/120x90/f00/fff.png&text=my+image" />
    <img src = "http://dummyimage.com/120x90/0f0/fff.png&text=my+image" />
    <img src = "http://dummyimage.com/120x90/00f/fff.png&text=my+image" />
    <img src = "http://dummyimage.com/120x90/ff0/fff.png&text=my+image" />
    <img src = "http://dummyimage.com/120x90/f0f/fff.png&text=my+image" />
    <img src = "http://dummyimage.com/120x90/0ff/fff.png&text=my+image" />
    
</div>

CSS

#images_wrapper {
    display:none;
}

JavaScript

var imgs = $("#images_wrapper > img")
var count = imgs.length;

imgs.load(function() {
    count--;
    if (!count) {
        $("#images_wrapper").show();
        alert('all done');
    }
}).filter(function() { return this.complete; }).load();