"Disable cache" only to start



a year ago
5 months ago


(Reporter: peterbe, Unassigned)


57 Branch

Firefox Tracking Flags

(firefox57 affected, firefox58 wontfix, firefox59 ?)



(1 attachment)



a year ago
Created attachment 8906071 [details]
Screen Shot 2017-09-08 at 2.56.04 PM.png

When you enabled "Disable cache" on the Network panel, it should disable any OLD cache but caching within the session. Like Chrome does it. 

Steps to reproduce:
1) Open Network panel and click on "Disable cache"
2) Open https://www.peterbe.com/css-blocking/bootstrap-lazyloadcsswithjs-vanilla.html

Expected results:
That the first load of bootstrap.min.css should be a 200 with an actual network fetch, but that the second request should be using caching.

Actual results:
There are two distinct 200 OK requests for bootstrap.min.css (same for that other jumbotron.css)

Also, I can confirm that the network traffic is real because I get these four lines in my server log when I refresh the page: - - [08/Sep/2017:18:55:02 +0000] "GET /css-blocking/bootstrap.min.css HTTP/1.1" 200 18617 "https://www.peterbe.com/css-blocking/bootstrap-lazyloadcsswithjs-vanilla.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:57.0) Gecko/20100101 Firefox/57.0" - - [08/Sep/2017:18:55:02 +0000] "GET /css-blocking/bootstrap.min.css HTTP/1.1" 200 18617 "https://www.peterbe.com/css-blocking/bootstrap-lazyloadcsswithjs-vanilla.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:57.0) Gecko/20100101 Firefox/57.0"

Comment 1

a year ago
The reason there are two requests at all for the same URL is to do with preloading followed by a piece of JS that changes the DOM and thus cause the browser to download it again. Yeah, that's nuts and a story for another bug but the point here is that the "Disable cache" should only be applicable for the stuff *before* the page is loaded.
Component: Developer Tools → Developer Tools: Netmonitor
This might be good improvement, but I wonder how often this issue comes up for real pages...?  Hopefully it's not that common to request the same static files many times over on a real site...?  Perhaps <iframe>s change the story a little, I'm not sure.
status-firefox58: --- → fix-optional
Priority: -- → P3


5 months ago
Product: Firefox → DevTools
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