2,415 karma · joined May 12, 2016
https://www.ietf.org/mail-archive/web/httpbisa/current/msg25...
https://bitsup.blogspot.co.uk/2016/05/cache-control-immutabl...
Rough summary:
> At Facebook, ... we've noticed that despite our nearly infinite expiration dates we see 10-20% of requests (depending on browser) for static resource being conditional revalidation. We believe this happens because UAs perform revalidation of requests if a user refreshes the page.
> A user who refreshes their Facebook page isn't looking for new versions of our _javascript_. Really they want updated content from our site. However UAs refresh all subresoruces of a page when the user refreshes a web page. This is designed to serve cases such as a weather site that says <img src="" ...
> Without an additional header, web sites are unable to control UA's behavior when the user uses the refresh button. UA's are rightfully hesitant in any solution that alters the long standing semantics of the refresh button (for example, not refreshing subresources).
In cases where there are multiple routes to complete a trip (eg remaining on one line vs making multiple connections for a faster journey) it was therefore previously not possible to determine what percentage of people chose which route.
> The representatives of WoSign and StartCom denied and continued to deny both of these allegations until sufficient data was collected to demonstrate that both allegations were correct. The levels of deception demonstrated by representatives of the combined company have led to Mozilla’s decision to distrust future certificates chaining up to the currently-included WoSign and StartCom root certificates.
Contrast this to WoSign's announcement:
> WoSign also made a careful investigation of these issues and issued a report on these issues, some problems have been clarified, and all problems are found in the first time and fixed. WoSign actively cooperate with the investigation and communication to guarantee the issued SSL certificate will not be affected in any way.
(https://www.wosign.com/english/News/announcement_about_Mozil...)
I'm interested to know how performance compares to the add-on, which uses a dedicated ELB per app (which is why it cost $20). On the one hand I would imagine switching to this new feature removes the need to pre-warm the endpoint (https://devcenter.heroku.com/articles/ssl-endpoint#performan...), but on the other could presumably introduce noisy neighbour issues.
"we will be rolling out exciting new features to it over the coming months" ...native Let's Encrypt support perhaps? :-)