Switches tend to be, push and they stay, or hold, and they let go when you do. So a 'clever' engineer, at Valeo I guess, reinvented the switch. Push and it returns to original position, but stays switched on. Normally an indicator gives a nice click when cancelling, and there's some feel too. But not with these, they self cancel very subtly. Are they ashamed? To cancel manually, push gently either way. But if you cancel manually at the exact time it cancels itself, it will give its clever three flashes as a 'lane change' signal. Not a big issue if cancelling the same direction as applied, but potentially dangerous if the opposite way. Many users than over-react and 'cancel' the opposite way, giving three flashes the other way. Following traffic are now ignoring your signals, so next time you need them, no-one reacts quickly enough. Genius.
They appear on Astra, Corsa, Vectra, BMW and MINI, so not just Vauxhall were taken in. Vauxhall reverted to normal ones for the Insignia, not been near enough a new Astra yet.
I'd like to meet the engineer responsible, and insert one of his switches into an orifice.
They used to confuse the learners, but you can get used to them, if never love them. Sorry, rant over now, time for a lie down.