Impossible to add pseudo element to canvases?

Question

So, I'm currently developing a map editor for a HTML5 game, and while doing so, I wanted to add some pseudo elements to canvases containing thumbnails for building blocks. But after an hour of experimenting and googling without succes, I simply couldn't make the pseudo element appear, I tried applying the css to a div and it appeared, so I guess there is something special going on with the canvas element?

Here is a simple example iv'e set up: http://jsfiddle.net/ZsHGE/

So, I'm turning to you, the all knowing folks here at stackoverflow, for an answer, is it impossible to add pseudo elements to the canvas element?

HTML: 
<!-- No visible pseudo candy :( -->
<canvas class="gimmeSomePseudoCandy" width="50" height="50"> :( </canvas>

<!-- pseudo candy appears! :) -->
<div class="gimmeSomePseudoCandy"></div>

CSS: 
.gimmeSomePseudoCandy:after { content:"Candy"; }

Answer 1

Replaced elements (such as canvas and img) do not currently work with pseudo-elements.

Note. This specification does not fully define the interaction of :before and :after with replaced elements (such as IMG in HTML). This will be defined in more detail in a future specification.

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