Why doesn't the font in Firefox load the first time?

Question

Fonts

The site has a non-standard PresentScript font. When the page is loaded for the first time, the font does not seem to be loaded and the default font (Verdana) is shown, after pressing F5 everything works. The bug is only in Firefox, in other browsers everything is fine. What could be the problem?

Answer 1

Check the headers of the font files provided by the server.
.htaccess has this(?):

AddType application/vnd.ms-fontobject  eot
AddType application/x-font-ttf         ttf ttc
AddType font/opentype                  otf
AddType application/x-font-woff        woff

Answer 2

Give the page a look, look at the browser console.
Perhaps there are some extensions. Is it on the same machine or not?

Answer 3

Look at the server logs/network tab in the firebug. If it does not show font requests, then try viewing them through Chrome. Look at the status and headers (specifically, Content-Type - one of those listed above should be given).