The font in my Facebook apps is real small and I can't do what I need to..Its only when using Firefox and not Internet Explorer...Help...

A couple days ago the font in the apps I am playing like Farmville, Puzzled Hearts and Cafe World went small and doesn't show the whole page either. Its not like that in Internet Explorer so that tells me its either a Facebook or Firefox problem. The Home page is the right size font I use. It's just so strange... Thanks and hope it can be fixed