1547587 - (stale-if-error) Implement stale-if-error (s-i-e) cache control directive

Status: UNCONFIRMED

(Core :: Networking: HTTP, task, P5)

Description

[brunoais]

RFC 5861 (https://tools.ietf.org/html/rfc5861#section-4) defines extensions for Cache-Control of stale content. This allows the browser to serve stale content.
One of them is

"stale-if-error" "=" delta-seconds
Allows a cache to server stale content when the server experiences an error.

It has been decided, in recent internal meetings that an implementation from Mozilla won't be happening in a foreeable future (source: https://bugzilla.mozilla.org/show_bug.cgi?id=995651#c7 ).
because the perceived benefit is deemed quite low and chrome appears not intending to implement it.
(source: https://bugzilla.mozilla.org/show_bug.cgi?id=995651#c11)

Still, I consider having a bug to discuss this exact thing something worthy. There's always a chance someone outside Mozilla is willing to fulfill it. Still, it is a P5 priority bug.