css - Cannot change the content of visited :before pseudo-elements

Question

I was trying to add some effects for visited links, then I got this problem.

Here is the code: http://dabblet.com/gist/5447894

Only Opera can successfully change the content of :before pseudo-elements. All other browsers are fail. Did I miss anything? Thanks

Answer 1

The allowed (= not ignored) CSS properties of visited links are color, background-color, border-*-color, outline-color and, column-rule-color (more under certain circumstances).

This is to prevent history stealing attacks. See this article for further details.

So you can, technically, set a :before pseudo class for :visited links, but it will be ignored and appears as if the links are not visited. This is not a bug, it's a feature ;)