Firstly, I am not using Add-ons. I used the Season Switcher to make it Christmas, too.
So, on with it, the Big Cookie, Santa, and buildings (cursors included) aren't showing up on my screen. Golden Cookies appear as usual, Reindeer too. It is indeed visual, as I can still click the invisible cookie and it adds to my click count. Buying stuff doesn't do anything except with the CPS. What I'm saying is that most stuff is invisible, but not absent. Will provide screenshot if asked. Oh and, I also tried refreshing the page. Don't ask about ascending, I don't have enough cookies to try it at the moment. I will ascend when I have enough, though.