How do specific browsers prevent downloaded fonts from being available to other applications

Question

As this is a stated requirement of the Web Fonts specification can someone explain to me how individual browsers handle this? I understand that IE temporary installs the font only for the period the font is required, but can find no mention of how this is handled for Firefox, Safari, Chrome, Opera etc.
Thanks,

Answer 1

I don't think browsers prevent that at all. It's not their task to. You can always use a browser (that includes HTTP utils such as wget) to directly download the font file and do with it what ever you want.

Edit: I can't find any reference to any requirement in the specification, just a appendix reminding the web author to observe the font licenses.