While starting up a Norse Mythology mash-up world, a friend and I noticed that the features from the new Nether Update are not present. I tried making a copy of the world, changing the settings to Experimental Gameplay, removing and redownloading the texture and template, and reseting the game altogether, all to no avail. The creative menu is no different than before, with only a changed name of the Zombified Piglin spawn egg, and a section for Nether Wart that consists only of the normal block. Keep note that it is not the texture that does not have the new features. It is specifically the mash-up world template itself that lacks them. Thank you!