WTF, there is no way that PC plod would allow that to make it on the roads, that is an instant accident just waiting to happen
Actually as long as none of it extends past the sides or rear of the car and it's properly attached it would be legal. It looks OK to me from that picture. You would of course have to tell your insurance company and they may have a different view of it.
My issue is that tha is the sort of thing that the police would stop and quetion you about. But my current bugbear, electric scooters seem to be ignored. I saw one on Friday. A woman on the pavement weaving in and out of pedestrians going to a primary scholl round 9AM. She had her kid stood on the platform in front of her
I don't have a motorcycle licence. I bet if I was doing the same thing on a unregistered & uninsured trials bike they would call the police and I'd get multiple charges. They don't bother with the scooters but its EXACTLY the same offences
(and no it wasn't a rental one which are "registered" and insured but are not allowed on the pavement or multiple riders)