Re: Specifying window.performance.now()

> "the number of milliseconds from the start of the navigation of the root
> document"
> Is the "start of the navigation" well enough defined? Should we link it to
> one of the other performance specs to tie it down absolutely?
> This also allows a cross-origin iframe to tell how long the parent has been
> alive, which I believe is not possible now. This is a slight privacy leak,
> which can easily be avoided. For instance remove "root" from the statement,
> or change it to "the topmost same-origin document", with a suitable
> definition of same-origin. I believe the second is better, it is useful for
> same-origin documents to have the same timestamps. For cross-origin
> documents this should normally not be required. This should also be recorded
> in the privacy section.

+1

Actually, I'd expect this to be relative to
https://dvcs.w3.org/hg/webperf/raw-file/tip/specs/NavigationTiming/Overview.html#nt-navigation-start
, which is unique for every document -- even same origin.

-Tony

Received on Wednesday, 29 February 2012 11:18:57 UTC