Publisher network: every CWV metric in the green

The Challenge

A publisher / media network with millions of monthly sessions was losing organic traffic on every Page Experience update. Field data in Search Console showed LCP averaging 4.8s, INP above 600ms on key article templates, and CLS issues across the ad layout.

Engineering

The critical render path was rebuilt: fonts preloaded with display: swap, render-blocking CSS inlined for above-the-fold, lazy-loading deferred for below-the-fold. Third-party scripts (analytics, consent, ads) were moved behind a deferred loader with a hard performance budget. Image priority hints, srcset and AVIF encoding were deployed via the CDN edge. The ad slot layout was rebuilt with reserved space to eliminate CLS.

Result

Field LCP dropped from 4.8s to 1.6s. INP dropped to 142ms. CLS to 0.04. PageSpeed Insights score moved from 28 to 92 on mobile. Critically, 100% of monitored URLs now sit in the "good" CWV cohort — and have stayed there across two subsequent core updates.