JSFiddle - React, Tailwind, and code Playground

HTML

<input id="chk1" type="checkbox" indeterminate="indeterminate"/>
<input id="chk2" type="checkbox" indeterminate="true"/>
<input id="chk3" type="checkbox" indeterminate="indeterminate"/>
<input id="chk4" type="checkbox" indeterminate="true"/>

JavaScript

$(function() {
    setTimeout(function() { // simulate long-running setup
        $('#chk3, #chk4').prop('indeterminate', true);
    }, 1500);
});