In case any of you were wondering what all the activity was about today, with strange behavior occurring around the icons and lightboxes and things, let me explain. This week is "Optimization Week" for me and I've been doing a lot of background changes to the site that are meant to make it much faster. None of the work really has a visible effect, but it does have a huge effect in terms of performance.
For example, all the icons you see here and there used to be individual files, and in order to load a page on ATP your browser had to download each and every icon and graphic individually.
On some pages, like threads, the microbadges that show up in our profiles can number into the dozens or even over a hundred different microbadges. Each badge forced a different connection to the server and that adds up to slow down your experience at ATP.
So, today I (mostly) finished my work of converting the microbadges and other icons into a single image. Your browser downloads the image once and then stores it in your cache, and then forever after it can display all the microbadges without ever having to download them again. The technique is called CSS spriting and it should have a huge impact on your performance. Even if you don't directly notice it, having a page load go from 1 second to 0.5 seconds is a gigantic improvement.
So, all the chaos from earlier today was worth the effort.