GProxy

GProxy is a Firefox/Thunderbird add-on (toolbar and status bar icon) that helps users to manage and switch proxy settings easily. It supports GPass, FreeGate, UltraSurf, Garden, and other proxy systems, with interface language in both English and Chinese.

GProxy is integrated into GPass. When you start Firefox for the first time via the yellow Firefox button, it will be installed in your Firefox. There is also a menu to install it in Thunderbird. You can uninstall it any time from the Tools>Add-ons menu in Firefox or Thunderbird.

With GProxy installed, you can choose GPass proxy to use GPass or None (i.e., no proxy) to restore direction connection. You only need to switch proxy if you start Firefox or Thunderbird via the yellow Firefox button or the menus next to it. You do not need to do so if your start Firefox or Thunderbird from the application list; just choose None (i.e., no proxy) for this case. For more explanation regarding the difference, please see Using GPass.

GProxy toolbar in Firefox:

GProxy status bar icon and display in Firefox: