Before Firefox got popular, it was once named Firebird. Here you can see the full browser interface. It also shows you the history about the browser.

Firebird also has a privacy settings like most browser do. Here you can see the basic history settings.

Here you can see the full Options menu of Firebird. It allows you to browser through different sub options.

Firebird also allows you to monitor JavaScript on a web page. Here you can see the JavaScript Console.

Similar to FireFox Firebird also has a plug-in feature. Like FireFox it is called extension.