Basically due to security restrictions in any other browser other than IE, I don't think this is possible without editing the registry.
Why you ask?
Such links could open network locations to malicious site hosters, thus practically giving them a backdoor to your network!
how to do it correctly?
I am not providing a link because I wouldn't recommend it but there is a solution to edit the windows registry to make these links work, however they will pop up using IE anyway so it kind of defeats the point!
what is the name of the syntax used to browse to shared folders?
I don't quite follow this one. But basically browsing to folders from your computer is simply called that: folder browsing. I'm not sure if there is a term for the double backslashes, double escape chars possibly? I'm not sure.
So to summise, it's a good idea that FF blocks it and I'm not sure how'd you get it working in FF fullstop.
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