How did CSS `content` property work for `img` element in WebKit?
问题 Long time ago there was a draft of CSS3 Generated Content spec which allowed the content property for any HTML element (not only ::before/::after pseudo-elements), without any formal restriction for empty or replaced elements. It was once supported by Opera Presto (1, 2) and, at least to some extent, by WebKit (3). By the end of 2011, WebKit's implementation of content for img element seemed to effectively convert it from an empty replaced element to non-replaced element like span (even its