How to Eliminate Render-Blocking Resources in Magento 2 for Faster Load Times
Render-blocking resources—like CSS and JavaScript files—can significantly slow down your Magento 2 store’s initial page load. These resources delay how quickly the browser can render your website content, directly affecting Core Web Vitals, particularly First Contentful Paint (FCP) and Largest Contentful Paint (LCP).
What Are Render-Blocking Resources?
Render-blocking resources are typically CSS files, JavaScript files, fonts, or third-party scripts that must be loaded and parsed by the browser before it can render any visible content on the screen. These resources delay the initial page load and negatively impact user experience, especially on slower networks or devices. Magento 2, by default, loads several such files across its pages, which can significantly block rendering and slow down the perceived performance of your store.
Enable CSS and JS Minification
Reduce file sizes to speed up load times by enabling minification in Magento's Developer settings.
Merge JavaScript and CSS Files
Combine multiple files into one to minimize HTTP requests and improve loading efficiency.
Move JS to the Bottom of the Page
Deferring JavaScript to the footer helps prevent blocking above-the-fold content rendering.
Use Asynchronous and Deferred Loading
Add async or defer attributes to non-critical JS files to prevent render delays.
Remove Unused CSS
Strip away unused CSS to reduce page weight and avoid unnecessary style blocking.
Inline Critical CSS
Inline essential above-the-fold CSS to speed up First Contentful Paint (FCP).
Leverage Full Page Caching and Varnish
Use full page cache and Varnish to serve pre-rendered pages quickly and boost performance.
Test Your Improvements
Use PageSpeed Insights, Lighthouse, or GTmetrix to verify reduced render-blocking and better Core Web Vitals.
Optimizing Magento 2 for performance is not just about server power—it’s about smart front-end practices too. Eliminating render-blocking resources is a powerful step toward improving user experience and SEO
For detailed blog :https://blog.meetanshi.com/eliminate-render-blocking-resources-in-magento-2/