Re: [CSS21][css-content] Resizing pseudo-elements with content: url()

On 2/18/15 3:58 AM, Daniel Tan wrote:
> However, CSS2.1 says nothing at all about replaced elements in the
> section on content: url(), which leads me to believe this is new to
> level 3.

It is.

CSS2.1 doesn't really clearly define the processing model of 'content' 
on ::before and ::after, but the informative examples in CSS 2.1, the 
fact that 'content' specifies a _list_ of things, and the desire for 
consistency has led to UA behavior being the following: the 'content' 
property specifies a list of things that become children of the ::before 
or ::after box.

-Boris