Since Webkit r40220 the posts on http://www.mac-bb.org (Powered by vBulletin® Version 3.7.4) aren't displayed anymore. If you log in, the posts can be seen for a fraction of a second and then the whole area where the posts are placed is grayed out. However, with all the other Mac browsers the site works as usual.
*** This bug has been marked as a duplicate of 23524 ***