Preview image disappears when container width is less than image width (Firefox)

I noticed in Firefox 3 (perhaps in Firefox 2 and IE as well - I never tested it) that the image displayed in the preview box disappeared if the width of the preview box was smaller than the image. I was puzzled as to why half of my images simply would never show up in that box, until I resized the browser window and noticed that they would show up if the preview box widened enough to accommodate the image width.

What's happening is, since the preview box has a left float in it (the log window), if it's not wide enough for the image, the image flows below the left float. But for some reason in this case the preview wrapper's overflow: auto; rule causes the image to simply vanish, rather than produce scroll bars... not exactly sure why that is.

Anyway, this patch solves the problem by moving the overflow: auto; rule from the #preview-wrapper selector to the #file-preview selector, and fits the #file-preview element to the height of its parent to make the bottom scroll bar visible.

I've tested the patch in FF2, FF3, IE6 and IE7.