Auto Proxy Retry от ftk

Sometimes websites block access depending on your ip address geolocation.
In this case having a proxy server to route your requests with different address is very helpful.
However it is often tiring to switch proxy on and off every time a websites decides to deny your request.
This extension automates that: it switches current tab to using a proxy if any of these conditions occur (customizable via addon preferences):
- server returns a certain http response code
- server returns a redirect response with location matching a certain regexp
- timeout occurs

Source code is available by downloading xpi addon file and opening it as zip.