The site has recently started doing this to me. It also has some pictures that were posted replace emoticons. Here's an example:

Similar stuff sometimes happens on my desktop PC (but here it tends more to happen with software and not with websites), it all comes from a bug in the GPU driver, that place the buffer in the same addresses as some icon etc is stored

Maybe something like that happen there too....

This site runs well on chrome books. I'll have to try it on my laptop soon.