a screenshot in which the directionality in the search box is messed
This bug is a bit complicated to explain.
First, it only seems to happen on Firefox. It doesn't happen on MSIE, Safari, Chrome and Opera. (Latest versions of all of them, on XP and Vista.) And it only happens with the Vector skin.
Enter an RTL Wikipedia, for example Hebrew.
Type the letter 'A' in the search box. There will be several suggestions: A, ABC, Allmusic, Associated Press, etc. But they won't appear correctly: it will be BCA, llmusicA, ssociated PressA. That is, the first letter goes in the end. (See the screenshot.)
Now click somewhere so that the drop-down will disappear and try it again. Now it will appear correctly.