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ModPageSpeed 2.0: AVIF, WebP, and critical CSS — up to 69% less page weight on the live demo

Canonicalize JS libraries

JavaScript

Redirects well-known library files to a shared, canonical, cacheable URL.

Filter canonicalize_javascript_libraries · Filter docs

A mod_pagespeed 1.15 filter. ModPageSpeed 2.0 applies it as part of one always-on pipeline, not as a separate switch.

Both frames render identically — that's the goal. The win is in the bytes and requests below, not the look. They're served live by mod_pagespeed 1.15 on demo-httpd-1.1.modpagespeed.com; the optimized frame applies only this filter. Right after a cache purge it may briefly match the original while the worker rewrites it — reload to see the result.

This filter needs configuration or content the public demo doesn't provide (e.g. an Analytics account id or a recognized JavaScript library), so there's no diff to show here — see the filter docs for what it does.

Run this on your own site

This is one of 47 filters mod_pagespeed 1.15 applies in place — self-hosted on Apache, nginx, and IIS. Install and run it: it optimizes right away and adds an X-PageSpeed-Warn: unlicensed header until you license it. A commercial license is required for production use.