Well, just like the title, Facebook's messages tab shows no content, only the link-buttons like New message, open Messenger or mark all as read. But, Solicitations and Notifications tabs work just fine. There's a picture bellow. I just installed Firefox today and it's already this way, I made no changes.

Also, for some reason, the pic i'm trying to upload (87kb) isn't completing. Never stops uploading. I have a commercial internet link of 240mb, so I believe it's not the problem.