As part of the Caves & Cliffs: Part I series, it includes features like Copper , Amethyst Geodes , Axolotls , and Glow Squids , as noted on the Minecraft Wiki. Major Fixes in this Patch According to the official Minecraft Feedback notes:
Resolved an issue where some worlds would not save properly, leading to lost progress. Minecraft [0100D71004694000] [v1.17.11]_Patched...
Addressed a bug that caused significant lag when players interacted with certain UI elements. As part of the Caves & Cliffs: Part