For some reason in firefox i cannot read embedded pdfs. it just says a plugin is needed to display the content and then has a link to download plugin. when i click it, it searches for a while and then says no suitable plugins were found. I tried the same thing in chrome and it read it automatically. I'm using ubuntu 12.04
mozplugger will allow you to open PDF as well as other things....
From Ubuntu's software Centers onlinne page(linked to above)
You can install it with the link provided or search for it in the software center directly...
One note however, this program doesn't always work seamlessly, it is supposed to open the PDF file inside the browser but sometimes it will open it in the