I'm playing uw control with kaheera as companion. After clicking the "apply styles" button a second kaheera appeared on my sideboard but the count of cards is still at 15. It's probably not counting the companion for some reason as a sideboard card.

I tried to enter the pioneer showcase event with this deck and due to this bug I don't have a sideboard but only the 6 first cards. That's a huge waste of my gold because I can't be competitive without a sideboard.