3 hours in already without any result. Basically I just want font awesome to work on Firefox. I've tried everything I have Access-Control-Allow-Origin: "*" in .htaccess. Also I tried putting it in httpd.conf of apache2. I run Apache version 2.2.14 on Ubuntu.

HTTP/1.0 200 OK => 
Date => Thu, 09 Apr 2015 07:15:44 GMT
Server => Apache/2.2.14 (Ubuntu)
X-Powered-By => PHP/5.4.39-1+deb.sury.org~lucid+2
X-Pingback => http://www.agripcn.com/xmlrpc.php
Link => ; rel=shortlink
Access-Control-Allow-Origin => *
Vary => Accept-Encoding
Connection => close
Content-Type => text/html; charset=UTF-8

This header checker tool shows it is set. Still Firefox shows no font awesome.

Also putting

<FilesMatch ".(eot|ttf|otf|woff)">
        Header set Access-Control-Allow-Origin "*"
    </FilesMatch>`

in .htaccess had no result.
sudo a2enmod headers is also activated

Ideas? I'm using wordpress for all my websites.