What is 'extra brake' in the button assignments - doesn't activate handbrake

The Opala Oldstock has a handbrake so I set my handbrake as 'extra brake' in the menu - but nothing happens when I use it.

 

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Thanks - that seems to mean the hand brake in this particular car ought to work.

 

That could be so, there are a few threads dotted around the forums about which vehicles should and should not have various extra controls such as cockpit adjustable brake bias, anti-roll bars and so on - that and reporting discrepancies between what the vehicle selection screen shows and what is currently implemented.