I just got a new computer, and I wanted to install all the nice shell extensions I had on my old one. Both of them are running Debian 7.5, and have gnome shell version 3.4.2.
The only difference I could find is that my new computer has a 64 bit version of Debian, and my old one has a 32 bit version.
But now, when I go to https://extensions.gnome.org/, all the extensions look greyed out and there are no install buttons.
Also, it looks like the user reviews just never load. Probably a related issue. They do load on my old computer.