Unbranded versions of Firefox are available to make testing of unsigned extensions possible.
By default, it is not possible to install unsigend extensions with Firefox.
To make automated testing of Firefox Extensions possible, TestingBot supports Unbranded Firefox.
This is a version which disables the signature checking of the extension, the Firefox branding is also removed from this version.
How to use
Typically you'll only want to use Firefox Unbranded for extension testing.
To test a Firefox extension, please see the following example:
DesiredCapabilities caps = new DesiredCapabilities();
caps.setCapability("version", "latest"); // for example