Personas, Safari and OSX 10.9 (Mavericks)

I've always used Safari as my browser for Personas work, until today. After upgrading to OSX 10.9 last night it seems that Personas in Safari is unable to save recorded scripts or load existing recordings onto a script button. Firefox works fine. Everything appears to work OK in Safari, as far as I can tell so far.

I'm guessing there's a new security feature in Safari preventing the Silverlight plugin from interacting with the Mac file system. I'm also hoping there's a way to turn it off so that Safari starts working again, but I haven't found it yet. If anybody has any suggestions, please comment below!

In the meantime, Firefox it is...