When I wrote about improving the images, one of the code blocks was for CSS, and two were for jQuery. Since it was more or less the first time I wrote jQuery, I thought it might have extra syntax over js, so I set the block's language to jQuery.
Sadly, the pygmentation gem was returning an error of unknown value "jQuery", or something like that. Silly me for not testing locally, but it would have been much more elegant for the gem to not colorize anything in that block, instead of returning a 500 if the language passed in is invalid.