So I just came across this problem in a recent project when I was using font-face to embed some fonts for a tumblr website. It worked fine in all browsers except for firefox… I tried everything to solve the problem and then turned to google and found this great article about how firefox prevents fonts from loading from another server. Since tumblr is put up on its own server I had to embed the fonts using a base64 encoding to embed the font directly into the css instead of from an outside source… annoying to say the least and a massive amount of code. You can easily get it from fontsquirrel.com for any font you upload.