Are CSS3 ::before and ::after pseudo elements supported by IE9 or not?

Question

On this MS compatibility table it says, IE9 does not support pseudo-elements ::before and ::after, but when I try it seems it does... see JSBin

Answer 1

The CSS2 pseudo-elements :before and :after, with the traditional single-colon notation, are supported by IE8 and later. They are not new to CSS3.

The double-colon notation, on the other hand, is new to CSS3. IE9 does support this new notation for ::before and ::after, and likewise for the CSS1 pseudo-elements ::first-line and ::first-letter. Going forward, however, no new pseudo-element may use the single colon syntax, and browsers (including IE) are expected to support the double colon syntax for all pseudo-elements.

I have no clue why that table says IE9 doesn't support the new pseudo-element syntax, because it certainly does according to the docs for the individual selectors linked above, and your test case. As well as, of course, this answer.