detailEventLoopPseudoCode

eventLoop = {
    taskQueues: {
        events: [], // UI events from native GUI framework
        parser: [], // HTML parser
        callbacks: [], // setTimeout, requestIdleTask
        resources: [], // image loading
        domManipulation[]
    },

    microtaskQueue: [
    ],

    nextTask: function() {
        // Spec says:
        // "Select the oldest task on one of the event loop's task   queues"
        // Which gives browser implementers lots of freedom
        // Queues can have different priorities, etc.
        for (let q of taskQueues)
            if (q.length > 0)
                return q.shift();
        return null;
    },

    executeMicrotasks: function() {
        if (scriptExecuting)
            return;
        let microtasks = this.microtaskQueue;
        this.microtaskQueue = [];
        for (let t of microtasks)
            t.execute();
    },

    needsRendering: function() {
        return vSyncTime() && (needsDomRerender() || hasEventLoopEventsToDispatch());
    },

    render: function() {
        dispatchPendingUIEvents();
        resizeSteps();
        scrollSteps();
        mediaQuerySteps();
        cssAnimationSteps();
        fullscreenRenderingSteps();

        animationFrameCallbackSteps();


        while (resizeObserverSteps()) {
            updateStyle();
            updateLayout();
        }
        intersectionObserverObserves();
        paint();
    }
}

while(true) {
    task = eventLoop.nextTask();
    if (task) {
        task.execute();
    }
    eventLoop.executeMicrotasks();
    if (eventLoop.needsRendering())
        eventLoop.render();
}

I like this. Thanks for sharing.