So not only has today's update (08/09/2020) not fixed the red box issue on the baby bullet, it would seem that the Union Pacific GP 38-2 also has the same issue
It has even before patch. MP36 have traction lock so the buged setup can accidentally appear, but GP38-2 don't support such feature so how this happen?
I know, it is not a functional bug, but it is confusing. If you are aware of the feature, you may think the throttle is blocked for some reason. Besides that, it is a stupid and sloppy bug that is so trivial it should not happen.