A third-party script facade is a static placeholder that loads no third-party JavaScript until the user interacts with it. In field data, swapping a YouTube iframe for a facade cuts LCP by 40% on mobile 4G. Here is the 2026 pattern for YouTube, Twitter, Maps, and chat widgets.
The Service Worker Static Routing API lets the browser bypass your SW fetch handler for chosen URLs, cutting cold-start latency and LCP. Hands-on guide with 2026 examples, Workbox interop, browser support, and the diagnostics I use to prove the win.
Learn how to cut your JavaScript bundle size with code splitting, tree shaking, Vite 6, vendor splitting, and performance budgets. Practical techniques with code examples to improve Core Web Vitals and load times.