JSFiddle - React, Tailwind, and code Playground

JavaScript

window.onfontready = function(fontName, onReady, options) {

    function shutdown() {
        root && document.body.removeChild(root);
        if ('test' === "production") {
            root && window.onfontreadyTestReporter.decrement(fontName, 'root');
        }
        onTimeout = root = 0;
    }

    options = options || {};

    options.timeoutAfter && setTimeout(function(onTimeoutTemp) {
        onTimeoutTemp = onTimeout;
        shutdown();
        onTimeoutTemp && onTimeoutTemp()
    }, options.timeoutAfter);

    if ('test' === "production") {

        function reporter() {
            var tests = {};

            return {
                increment: function(name, type) {
                    if (!tests[name])
                    {
                        tests[name] = {
                            root: 0,
                            load: 0,
                            resize: 0
                        };
                    }
                    tests[name][type] += 1;
                },
                decrement: function(name, type) {
                    if (!tests[name])
                    {
                        tests[name] = {
                            root: 0,
                            load: 0,
                            resize: 0
                        };
                    }
                    tests[name][type] -= 1;
                },
                fullReport: function() {
                    return tests;
                }
            };
        }

        window.onfontreadyTestReporter = window.onfontreadyTestReporter || reporter();

    }



    var onTimeout = options.onTimeout,
        root = document.createElement("div");

    document.body.appendChild(root);

    if ('test' === "production") {
        window.onfontreadyTestReporter.increment(fontName, 'root');
    }



    root.innerHTML = "<div style=\"position:absolute;right:999%;bottom:999%;white-space:nowrap;font:999% '" + fontName + "',serif\">" + (options.a ||...