if you want to find out which casinos are having Christmas bonuses/promotions try checking the gambling site's ANN thread here in the forum, they usually post if they are having Christmas bonuses/promotions. also, I remember reading on crypto.games ANN thread that they are having daily challenges and giveaways as part of this month's Christmas bonuses/promotions.
That's true, the announcement discussion thread of all the available gambling platforms available on this forum could also be put into consideration, but I must make this in addition that OP should try as much as possible in reading through the conditions that comprises some of these offers before applying, bonus sometimes is nothing free because you will have to work your way out for it before being eligible.