An area in red on the righthand side (appears to be the download area) of the page is overwritten with two sets of text making it unreadable.
Created attachment 11574 [details]
Created attachment 11575 [details]
Strict mode - no overlap
In strict mode, the table clears the floats, but in quirks mode it doesn't. Adding <!DOCTYPE HTML> to the original page fixes its layout. Firefox's behavior (in both modes) is like WebKit's quirks mode (which is perhaps the reason for the quirk).