Thomas can too and has given me a heart attack on more than one occasion when he has appeared between the seats half way up the M6
. I didn't find anything that would help tbh and what worried me most was if we put anything restrictive over the clasp what would happen if we had to get him out in an emergency?
or if fire men couldn't figure it out if we crashed etc
so I didn't go down that road. I have basically just had to keep telling him off for messing with it and he is allowed to do it when the car stops only now so he has learned to wait. It's not perfect because as soon as the car comes to a stop he starts to get out so I have to remember to tell him NO at traffic lights etc.
Sorry this isn't much help but maybe if like Thomas you allow him to let himself out when you get home (or wherever you're going) and praise him for staying in he will hopefully get the idea.
xx
