Firefox 13 Portable Fonts

Firefox 13 Portable is not displaying fonts from the PortableApps font folder.

I have a local web page using one of those fonts. It displays fine in IE, but not in Firefox. It also appears on Firefox 13 on my home computer.

I also have NexusFont in operation, from my flash drive, and fonts in it are working in IE, but not Firefox Portable.

Other applications on my flash drive can use fonts from both locations, including LibreOffice Writer.

Please help.