We experienced an interesting issue for one of our customers today. The fonts they had specified using the @font-face technique, would not render in Firefox. The fonts would show up fine in Chrome, Safari, and IE, but in Firefox 3.5 the fonts would not render.
First, I forced the stylesheet to not be loaded from the CDN, this proved our hypothesis, if the call to the stylesheet was from the same domain, Firefox would render the font fine.
That was nice and all, but I didn’t really like that, it just seemed silly to tell a plugin to send files to the CDN, except one.. all because only one item from the CSS was not working properly. So, I added the following condition inside the Apache configuration..
Header set Access-Control-Allow-Origin *
This sets the header on the Apache side. We use MaxCDN which honors the headers sent by the origin, so the header is passed through and everything works.