consider setting cache-control:immutable

[kralo]

which is a cache-control extension implemented already in firefox. I think this is reasonable, as you already set a large cache expiration date Cache-Control: public, max-age=30672000

This could help reducing calls to the server resulting in 304 not-modified and thereby also reduce some privacy issues (less requests - less traceability)...

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[drewfreyling]

This is a good idea but might not be of real benefit until it is supported by more browsers as it is just a bunch of wasted bytes unless you use a recent version of Firefox.
Chrome doesn't seem to be in a hurry - https://bugs.chromium.org/p/chromium/issues/detail?id=611416

[PeterDaveHello]

cc @cdnjs/owners @terinjokes

[terinjokes]

This looks pretty cool.

I don't think we should implement it until I change the backend to reduce the update failures we have from time to time (and, perhaps, officially supporting "latest")

[dima74]

Hello! What about adding Cache-Control: immutable only when user-agent is Firefox?

[PeterDaveHello]

Hi @terinjokes, I think it'll be great to enable it no matter it the backend on Cloudflare side changes as this can really help improve performance by reducing the cache validation, am I right?

[MattIPv4]

@PeterDaveHello Chrome still does not have this implemented, should I raise this to Cf to ask them to set Cache control to be immutable when a Firefox UA is detected?

[MatthewSteeples]

Everyone apart from Chrome (and probable IE) implement this now

[MattIPv4]

@MatthewSteeples Yeah, I think it best we implement it as it should improve performance. I will contact Cf and post any updates here :)

[MattIPv4]

@xtuc would you be able to help with getting this added?

[xtuc]

According to https://caniuse.com/#feat=mdn-http_headers_cache-control_immutable the support is pretty low

[MattIPv4]

Currently, we send cache-control: public, max-age=30672000. Looking at https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control#Caching_static_assets it should be safe to append , immutable.

https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control#Extension_Cache-Control_directives notes that if a UA doesn't recognize immutable, it should just be ignored, so it'd fall back to the long max-age we are sending.

(I'm no expert on this though)

[xtuc]

@MattIPv4 that sound right. I sent the header to my Chrome and it didn't fail. That said, I'm not sure how to check that it works

[MattIPv4]

@xtuc Simple. Just wait a year and see if it expires. /s

[MattIPv4]

Chrome's dev tools should show if the resource was fetched from cache or not, but I'm not sure of any way to really confirm how long it's planning to hold the resource for in cache.