In Competitions, most "Challenge" buttons are *black, but many are purple. What do the different colors mean, in particular the purple.
There are green "Challenge" buttons? I see purple and black. And a big green "Launch event" button. Anyway, in "premium" challenges (those that aren't "free"), in order to "challenge" someone's ghost you need to own both their car and their livery. Purple means you don't own either the car or the livery or both. Black means you have everything you need, you can click it and drive.