Some websites/forums ask you to register before you can see its content. Here is a firefox tweak to bypass registration process and directly see the content.
Write about:config in firefox’s address bar and hit enter.
If it shows you a message “This might avoid your warranty!”. Press the button “I’ll be careful, I promise”.
Now in the filter box write general.useragent.override.
Double click on the preference name general.useragent.override from the list below the filter box.