The background images set on the root element will blend with an initial white backdrop. Instead, they should blend with the background-color of the root element, or, if no background-color is specified for the root element, background images should blend over an initial transparent backdrop.
The spec states:
Each background layer must blend with the element’s background layer that is below it and the element’s background color. Background layers must not blend with the content that is behind the element, instead they must act as if they are rendered into an isolated group.
Created attachment 233896 [details]
I attached an html demonstrating the issue.
Here is a discussion on public-fx and www-style related to this use case: http://lists.w3.org/Archives/Public/public-fx/2014AprJun/0175.html.
Created attachment 233980 [details]
Simon, could you please have a look at this patch?
Comment on attachment 233980 [details]
Clearing flags on attachment: 233980
Committed r170841: <http://trac.webkit.org/changeset/170841>
All reviewed patches have been landed. Closing bug.