It doesn't work for me on Safari Version 6.0.4 (8536.29.13) with no Flash installed on OS X Mountain Lion.

Javascript Console says: TypeError: 'undefined' is not an object (evaluating 'this.htmlBridge.style')

I'm guessing this is because I don't have flash installed.

Unfortunately it depends on Flash due to OS level copy functionality. Browsers doesn't allow JavaScript to access copy functionality.