my last cat used to dribble a little when she purred, but rather bizzarely only when she was being fussed, if she was splodged out in front of the fire purring away to herself then she didn't dribble![]()
I think they dribble when being pampered (especially when they start kneading) as it harks back to when they were kittens and the kneaded their mum for milk!
One of mine used to do it quite a bit lol