JSFiddle - React, Tailwind, and code Playground

HTML

<button class="create">Create</button>
<button class="delete">Delete</button>
<div id="parent"></div>

JavaScript

var parentDiv = document.querySelector('#parent');
var actions = {
    create: function createStuff() {
        var frag = document.createDocumentFragment();
        for (var i = 0; i < 10000; i++) {
            var child = document.createElement('div');
            child.id = i;
            child.textContent = i;
            frag.appendChild(child);
        }
        parentDiv.appendChild(frag);
    },
    delete: function deleteStuff() {
        while (parentDiv.children.length) parentDiv.removeChild(parentDiv.firstChild);
    }
};

Array.prototype.forEach.call(document.querySelectorAll('button'), function addListener(el) {
    el.addEventListener('click', function handler(event) {
        console.log(event.target.textContent + '!');
        actions[event.target.className]();
    });
});