[whatwg] Resource loading in browsing context-less Documents

Anne van Kesteren annevk at annevk.nl
Fri Oct 5 01:23:44 PDT 2012

On Fri, Oct 5, 2012 at 8:00 AM, Ian Hickson <ian at hixie.ch> wrote:
> This is specced. The UA is allowed to send the HTTP request (that's a
> truism, of course, nothing stops the UA from sending any arbitrary HTTP
> request at any time), but there's no in-DOM visible effect of that
> request, because event loops don't process tasks for documents without
> active browsing contexts, so the tasks that the "fetch" algorithm
> generates never get executed. (A clever UA can notice this and delay
> (forever) the HTTP requests, since the "fetch" algorithm allows you to
> wait an arbitrary amount of time before doing the request.)

Note that you can append such an <img> to a different document later
(e.g. the one that executes the script) so fetching it is probably


More information about the whatwg mailing list