I just manually look at it in the inspector's network tab. The "template" is already loaded and you can see how big the JSON is and optimize that if necessary.

I just manually look at it in the inspector's network tab. The "template" is already loaded and you can see how big the JSON is and optimize that if necessary. You can also turn on redraw debugging with the React debugger if necessary, but that's not usually a bottleneck. The fresh page load is usually the worst case scenario, so inter page navigation once the framework is already cached is generally much faster. Combined with preloading of the JSONs on hover, it can be nearly instantaneous for the user.