Is extend_cache_css enabled by default?

Yes. extend_cache_css is in CoreFilters, the default RewriteLevel, so it runs unless you turn it off with DisableFilters.

How do I turn off extend_cache_css?

Add ModPagespeedDisableFilters extend_cache_css on Apache or pagespeed DisableFilters extend_cache_css; on nginx. On IIS, add pagespeed DisableFilters extend_cache_css to pagespeed.config.

filter · CSS filters

Extend cache for CSS (extend_cache_css)

Q: What does the extend_cache_css filter do?

Core filter, one of the three members of extend_cache. Rewrites URLs to content-hashed .pagespeed.ce. URLs that the module serves with a one-year Cache-Control max-age, so browsers keep stylesheets for a year and still pick up every change (a changed file gets a new URL). Use it when the origin cannot set long cache lifetimes itself; under CoreFilters it is already on through extend_cache.

Category:: CSS
CoreFilters:: Yes
OptimizeForBandwidth:: No
Risk:: Generally safe

Core filter, one of the three members of extend_cache. Rewrites <link rel="stylesheet"> URLs to content-hashed .pagespeed.ce. URLs that the module serves with a one-year Cache-Control max-age, so browsers keep stylesheets for a year and still pick up every change (a changed file gets a new URL). Use it when the origin cannot set long cache lifetimes itself; under CoreFilters it is already on through extend_cache.

How it works

Disabling it leaves extend_cache_images and extend_cache_scripts on. The one rule to respect is the general one: HTML and the resources it references must share one configuration (see Virtual hosts). Live demo: extend_cache.

When to use it

In CoreFilters, the default RewriteLevel: it runs unless you disable it.
Also switched on by extend_cache.
Risk rating on these docs: Generally safe.

Risks

The CSS filters page lists no specific risks for this filter. If a page misbehaves with it, DisableFilters extend_cache_css turns it off for the scope you set it in.

Configuration

Enable it in the module configuration, at server, virtual-host or location scope:

Apache

ModPagespeedEnableFilters extend_cache_css

nginx

pagespeed EnableFilters extend_cache_css;

IIS (pagespeed.config)

pagespeed EnableFilters extend_cache_css

It is on by default under CoreFilters; to turn it off:

ModPagespeedDisableFilters extend_cache_css   # Apache
pagespeed DisableFilters extend_cache_css;   # nginx
pagespeed DisableFilters extend_cache_css   # IIS

On the worker

The worker runs its own pipeline, configured by flags. Its equivalent of this filter is the cache extension transform. Always-on under pagespeed on;.

Scoping, ForbidFilters and the thresholds filters read: Choosing filters .

Frequently asked questions

What does the extend_cache_css filter do?: Core filter, one of the three members of extend_cache. Rewrites <link rel="stylesheet"> URLs to content-hashed .pagespeed.ce. URLs that the module serves with a one-year Cache-Control max-age, so browsers keep stylesheets for a year and still pick up every change (a changed file gets a new URL). Use it when the origin cannot set long cache lifetimes itself; under CoreFilters it is already on through extend_cache.
Is extend_cache_css enabled by default?: Yes. extend_cache_css is in CoreFilters, the default RewriteLevel, so it runs unless you turn it off with DisableFilters.
How do I turn off extend_cache_css?: Add ModPagespeedDisableFilters extend_cache_css on Apache or pagespeed DisableFilters extend_cache_css; on nginx. On IIS, add pagespeed DisableFilters extend_cache_css to pagespeed.config.

combine_css — Combine CSS
compute_critical_css — Compute critical CSS
fallback_rewrite_css_urls — Fallback CSS URL rewriting
flatten_css_imports — Flatten CSS @imports
inline_css — Inline CSS
inline_google_font_css — Inline Google Fonts CSS
inline_import_to_link — Convert @import to link
move_css_above_scripts — Move CSS above scripts

This page is drawn from the extend_cache_css entry on CSS filters. Every filter in one table: PageSpeed filters.