It's after the main content.
Works correctly in Firefox Beta 11. Broken in Aurora 12.
After running the mozregression tool.
Last good nightly: 2011-08-21
First bad nightly: 2011-08-22
Oh, taintEnabled. This is a known bug with old MediaWiki version browser-sniffing code. The site needs to be fixed...
I opened a bug report on their system:
Declared fixed on their Web site