The 5th pre-release was released recently.
A lot of item, mob, and biome ID's were renamed to be more consistent with the names that you see ingame normally. There are tons of ID's that were renamed (and more potentially to be added onto the Minecraft Wiki, which is where I got this information) and I'm not going to list all of them here. So instead I'll just link the Minecraft Wiki page that contains this information. https://minecraft.gamepedia.com/1.13-pre5