I'm using the JSBlacklist extension in Safari: http://homepage.mac.com/drewthaler/jsblacklist/ I'm also using Highslide JS on my site: http://highslide.com/ When I enable JSBlacklist, it seems to break Highslide. You can try on my site with the screenshots at the bottom: http://erikhinterbichler.com/software/herald/ I reported this to the JSBlacklist developer, and he believes it's a bug in Webkit. I'll reproduce the email he sent me below: ---- Thanks for the report! From a quick test, it looks like the same problem appears with other Safari content-blockers too (like Facebook Cleaner and Safari AdBlock). So it seems like a WebKit bug rather than a JSBlacklist bug. In fact, it sounds like a bug I filed recently: WebKit bug #44529. There's something in the way that Safari handles content-blocking (via the beforeload: listener) which affects page rendering in a subtle way. The problem occurs even if you create a do-nothing extension which does nothing but install a completely empty beforeLoad listener. Anyway, to prove this I created an empty BeforeLoad.safariextz, which I attached to that bug. It breaks cgbg.com, where I got the original report, and it appears to break your page too.
<rdar://problem/8401376>