So I'm building a web app, and I want to emulate a network failure in browser to see if the client side javascript handles it gracefully. I know I can just disconnect my network connection, but that also disconnects my email, pandora, skype, all things that are marginally vital to my non-productivity. Is there an easy way to kill network communication for just one tab in either of these browser? Or (I'm in linux) can I block a single pid from network communication while still allowing the rest (even if it's the same program) through?
Edit: Shoot, I just realized that I'm working on localhost, and that may not apply for what I'm asking for.