> Check all Mink*Driver?

Mink have drivers for multiple testing programs and Selenium is one of them (see https://github.com/Behat for any repository that ends with `Driver`). All drivers implement united `DriverInterface`, which tells what is returned and in which cases and they all extend `CoreDriver` class, which implements this interface.

> What is "BC"?

It's backwards compatibility. Right now Selenium2Driver tests in `master` pass. Did they also pass after this change?