Visualizing the Hidden CPU Cost of Modern JavaScript Frameworks
A while ago, I noticed something that didn't quite make sense. On paper, today's internet connections are incredibly fast. Many people have access to hundreds of megabits per second, and modern processors are vastly more powerful than those from a decade ago. Yet it's still common to open a website, see most of the interface appear almost immediately, and then wait another second or several seconds before buttons respond or menus become clickable. The page looks finished. It just isn't usable. That made me curious about what the browser was actually doing after the download had already completed. The Observation When most people think a website is loading, they imagine data traveling across the internet. That's only part of the story. Modern web applications often send HTML, CSS, JavaScript, images, fonts, analytics scripts, and framework code to the browser. Downloading those files is only the beginning. After everything arrives, the browser still has to parse, c...