The text of a very long tag in the Recent Searches box will spill over onto the rest of the screen, and can run over onto the text of a post's wiki when opened on the post page. It's not a big problem, because the wiki page can simply be opened in the wiki itself to read any text that was covered up. Not sure how to fix it, other than truncating a tag over a certain number of characters with an ellipses or substituting a shorter aliased tag like /watamote for the longer tag if the tag is over a certain number of characters.
It looks like this:
http://imgur.com/wIg3OkR