Extensions menu disabled on Mac

I can't click on that menu option it is disabled.

Version 2.0.8 Twoflower (Intel 64bit) Compiled by fkuehne with clang 4.2 (clang-425.0.24)

OS:

OSx 10.8.4

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information