Specifically, I awent to the beta 1.19.50.21 to play with the new bamboo stuff, the camels, the chiseled bookshelf and the signs, but there are no such items and entities. They aren't in the creative or survival inventory and I can't obtain them with commands, as they don't appear in any way. I went to check the version to make sure I was in the right beta, and it was. I have undownloaded 3 times, left and rejoined beta 4 or 5 times, and still won't work.