title: How to inject code into facebook/google web page using extensions?
body: <p>I am a newbie to extension development. I am trying to create an extension where i can inject code into a webpage. I have been trying to do this using google chrome content scripts. But i have been unable to do this on facebook.com or google.com. It seems to work on yahoo.com. Is there a reason for this? How can i get around this?</p>