should impede it («Not all fonts installed on your computer are available to webpages»), but I am not sure, as I do not know the exact "which fonts to expose" rule.
Edit: in theory, it should allow only "«base»" fonts and not user installed. In practice, more details would be useful.
Edit: in theory, it should allow only "«base»" fonts and not user installed. In practice, more details would be useful.