I put on a 2XP boost and got some challenges done… the payouts appear broken but apparently they do give 2XP, see the reply below.
It’s working for me. It still says the normal XP amount to the right, but if you watch it go up and do the math, it will go up by 2x the Challenge XP.
Oh I didn’t realize that, I thought because it displayed the wrong amount that it wasn’t working.
I did watch the progression and saw boo doubling. Got a +50xp for playing my 6th or 7th game, and my XP prints only jumped 50. Seems buggy.
it only changes after you get them.