Programming Tutorials

  You have optimized your React components, memoized expensive calculations, and minimized your bundle size. Yet, your Core Web Vitals report shows an Interaction to Next Paint (INP) score hovering in the "Needs Improvement" (200-500ms) or "Poor" (>500ms) range. The culprit is rarely your application code. In ad-supported publishing, the bottleneck is almost always the "Header Bidding" wrapper (Prebid.js) or the Google Publisher Tag (GPT) library. These scripts execute computationally expensive auction logic, parse massive JSON payloads, and force layout recalculations—often strictly on the main thread. This article details how to dismantle monolithic ad execution using modern scheduling APIs ( scheduler.yield ), significantly reducing Main Thread blocking time and salvaging your INP score without sacrificing ad revenue. The Root Cause: Why Ads Destroy INP To fix the problem, we must understand the mechanics of the browser's Main Thread. The Main Th...