Core Web Vitals: four Plesk extensions for server-side fixes

Anyone running shared hosting knows it well: Core Web Vitals aren't fixed just by optimising themes and plugins — often the real work starts with server configuration. Plesk, in its official blog post dated 13 August 2026, has lined up four extensions that act on caching, DNS and the web server to boost LCP (loading), INP (responsiveness) and CLS (visual stability) scores.

Where to start: the baseline

Before touching any configuration, you need a reference score. The Google PageSpeed Insights extension gives the same score Google uses to judge your site, scans each domain, produces separate scores for desktop and mobile, and lists specific fixes ranked by impact. The Pro version adds bulk scanning across all domains on the server and automatic daily rescans, handy if you manage multiple sites.

Browser-side and CDN caching

For the quickest wins, Plesk points to Speed Kit, developed by Baqend GmbH: once activated, it adds a Service Worker to the site, which routes all requests from the backend to a fast cache kept in sync with the site. On the official Plesk marketplace the current release is 2.6.0 and requires Plesk 18.0.30 or later; for WordPress sites running WP Toolkit it works as a one-click solution to speed up the site.

For those with international traffic, DNS Integration for Cloudflare connects Plesk's DNS records to the Cloudflare network and lets you enable CDN and proxy mode without leaving the Plesk dashboard, cutting the physical distance data has to travel and also automating the DNS challenge for wildcard Let's Encrypt certificates.

The web server leap: LiteSpeed

When caching and CDN aren't enough on their own, there's still the web server upgrade. The LiteSpeed extension, version 2.4.2 and compatible from Plesk 17.0 upwards, requires a LiteSpeed Web Server licence: you can request a trial licence through the extension's interface or buy one by entering the serial number.

Quick comparison

Extension	What it does	Constraint/licence
Google PageSpeed Insights	Measures baseline LCP/INP/CLS per domain, desktop and mobile	Pro version for multi-domain scans
Speed Kit (Baqend)	Service worker that serves assets from a cache close to the browser	v2.6.0, requires Plesk ≥18.0.30
DNS Integration for Cloudflare	Enables Cloudflare CDN and proxy from the Plesk panel	Requires a Cloudflare account
LiteSpeed Extension	Replaces/complements Apache with an event-driven web server	v2.4.2, separate licence from LiteSpeed Technologies

For those starting from scratch, the suggested order remains: establish a baseline with PageSpeed Insights, then caching (Speed Kit) or CDN (Cloudflare) depending on the geographic spread of your traffic, and only as a last step move to LiteSpeed if INP stays high under real-world load.