Eliminate Legacy JavaScript Polyfills

How to optimize igd.happythoughts.in

Next.js SiteScore: 46/100Analyzed May 2026Re-analyze this site

Eliminate Legacy JavaScript Polyfills

Medium Impact+8 points estimated

Why It Matters

Unnecessary polyfills add 14KB and delay LCP by 150ms for modern browsers.

How to Fix

Update your Next.js target in next.config.js to exclude legacy browsers (set browserslist to modern browsers only). Remove polyfills for Array.at, Object.hasOwn, and String.trim methods which are widely supported. Use differential serving to serve modern JS to capable browsers.

0Poor

What This Score Means

A score of 46 falls in the "Poor" range (50-89). While it is better than poor (0-49), you should aim for 90+ to provide an optimal user experience and maximize SEO benefits.

This site is slower than approximately 35% of similar sites. The main issues affecting performance are image optimization, JavaScript execution time, and layout stability.

Addressing these issues could improve your conversion rate by 15-20% and boost your search engine rankings.

Core Web Vitals Analysis

LCP

Largest Contentful Paint

77.0s
Poor

Good: < 2.5s

Measures how long it takes for the main content to appear on screen

INP

Interaction to Next Paint

768ms
Poor

Good: < 200ms

Measures how quickly the page responds to user interactions

CLS

Cumulative Layout Shift

0.00
Good

Good: < 0.1

Measures visual stability - how much content shifts during page load

AI Performance Analysis

This Next.js/React site has severe performance issues with a score of 46/100, indicating poor user experience. The biggest problem is an enormous 11MB JavaScript bundle that's 86% unused code, causing a catastrophic 77-second load time for the main content and making the page unresponsive for nearly 2 seconds. The site is loading far too much unnecessary JavaScript upfront - reducing this bundle size through code splitting, removing unused dependencies, and implementing lazy loading could dramatically improve performance by 50+ seconds and make the site actually usable for visitors.

Other Optimization Recommendations

Remove Unused JavaScript Code

High Impact+25 points estimated

Why It Matters:

Unused JavaScript wastes 11MB of bandwidth and delays LCP by 55.8 seconds while blocking interactions.

How to Fix:

Use Next.js bundle analyzer to identify unused code in your chunks. Enable tree shaking in webpack config and remove unused dependencies. Split the massive 03j82jtbff3mp.js chunk using dynamic imports for route-based code splitting.

Optimize JavaScript Execution Performance

High Impact+18 points estimated

Why It Matters:

JavaScript execution blocks the main thread for 2.8 seconds, creating a 770ms potential input delay.

How to Fix:

Break up long-running tasks by using React's concurrent features like startTransition. Move heavy computations to Web Workers. Implement code splitting at component level using React.lazy() and Suspense for non-critical features.

Keep Your Site Fast After Optimization

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