100917 - use cache if HTTP server is unreachable

Status: VERIFIED DUPLICATE of bug 20838

(Core :: Networking: HTTP, enhancement)

Description

[Mark Slater]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (Windows; U; WinNT4.0; en-US; rv:0.9.4+) Gecko/20010918
BuildID:    2001091803

Let's say you visit a site on a regular basis. Let's say that site can't be
reached today. Moz should pop up a dialog window saying "The site cannot be
found because of [reason]. I have an older version from [date] saved in cache.
Display that instead? - |Yes| - |Retry loading the site from net| - |No|"

Reproducible: Always
Steps to Reproduce:
Find a site you visit often that 404s. Especially easily seen trying to reach
any popular site after the WTC tragedy.

Actual Results:  Moz sez "Host unreachable" (or similar) and presents me with a
white page.

Expected Results:  Noticed that a) the site is unreachable, yet b) found an
older copy of the site in the cache. Then offer to show said older version,
pulled from the cache.

I realise the obvious dangers when/if this gets implemented, eg. having for
instance the CNN website 404, subsequently being presented with really OLD news,
and the user thinking that it's actually up-to-date news s/he's seeing.

Comment 1

[Bradley Baetz (:bbaetz)]

Host-unreachable is not a 404. 404 means that the file doesn't exist on the server.

4.x did this.

Comment 2

[R.K.Aa.]

*** This bug has been marked as a duplicate of 20838 ***

Comment 3

[timeless]

vrfy dupe

Comment 4

[benc]

corrected summary.