Check that there are no holes left by the removal of nsIContentPolicy
To close #3882 (moved) , we should run more tests to ensure that no HTTP requests are escaping redirection.
We have done a bit of this without plugins, but we should also perform more and with plugins. Methodology:
Run a wireshark capture with the BPF set to "port 80" (or a protocol-level equivalent?).
Do a lot of browsing.
Filter out the HTTP Request packets.
See if any of them should have been rewritten.