When trying to see the upvotes and downvotes details of a post (not just the sum of them) I noticed that a horrible
0loading... text appears for less than a second and is then replaced by the actual votes. I managed to take a screenshot.
Even the text of the question is pushed to the right. I could also reproduce this behaviour by clearing the cache of the browser, refreshing the page and finally trying to see the detail again.
NOTE: I'm using FireFox 11.0