Just been experimenting, and it looks like the Ghostery security plugin clashes with Viglink and stops the links working
Its not Adaware or No-Script - they don't seem to have any effect on it. But if you disable Ghostery things start working again.
Ghostery also exists for IE and Chrome, so the same can be expected there.
I can't see a way so far of bypassing Viglink to allow the links to load normally