The "User History" screen moderator-tool has an interesting UI bug on Firefox with Linux. Haven't checked FF on other platforms, but it does do it on multiple FF/Linux machines of mine.
First of all, compared to how the screen looks in Opera 11, the Date column is immediately after the [change filter] link, rather than on the next line. I can reproduce this in SeaMonkey 2.0 (another Mozilla browser, uses Gecko same as FF) on Windows. On IE8/Windows, it looks normal: