No Alternate Blocks?

Well, for some reason, since 1.10, Alternate Blocks won't work. There's no option to toggle it, and it doesn't work either. Is this a "feature" as in, you've removed them, or is this a bug?
Because i heard that the toggle was removed, but it was on by default and you could toggle it by using resource packs, but i don't use any.
Help?