Easy way to produce this bug:

1) Start qualifying and add AI-drivers who are driving with MRT, FBM, FOX, FO8 or BF1
2) Wait until the end of lap 4 or 5 when AI-drivers return to pit lane and turn off their engines
3) Hit/Touch them and watch "This car does not have a handbrake"-message flooding on chat

It doesn't matter who hits your AI-drivers. Even somebody else can hit your AI-drivers (as long as AI-drivers have turned off their engines and are using a single-seater as a car) and you still get that message flooding on chat.

Hi, which version are you on?

Edit: Same, can reproduce on 0.6M.

I'm using 0.6M

Don't mind me, just casually confirming the bug in 0.6n4