Minecraft Snapshot 24w05a
Along side many technical changes, the new experimental feature for Trial Chambers, the Vault Block appears!

In this weeks snapshot, we get a bunch of technical changes about the region file compression that was recently implemented. It seems like Mojang is opening up the option for developers to implement custom compression for the region files. If this is something you are interested in I suggest going to check out the full write up.
Vault Block
Along side a new texture change for the Trial Key, we finally get our first in game peek of the Vault block.

Finding and Using the Vault block
The Vault block is found throughout the new Trial Chamber structure. To open a Vault, a player must have acquired a trial key. When approaching a Vault the key hole will open and all the possible items will cycle around inside the cage. Each Vault can only be opened once per player. If at least one player is nearby the key hole will be open and a stream of orange particles will flow from the player to the Vault.
Once all nearby players have looted the Vault, the key hole will close. Vaults currently reuse the same loot table that the previous Trial Chambers reward chests use. This loot table will most likely change as we get closer to a full release of the trial chamber.
Features
The rewards from the Vault are ejected out the top. The rewards are randomized from its loot table each time its unlocked. The Vault cannot be crafted or obtained in Survival much like a spawner, and does not drop anything when mined. The Vault is explosion resistant and cannot be moved with pistons.
Final Thoughts
As mentioned in my previous post from Minecraft Monthly, I think this is a neat design choice to allow for less competition over treasure chests. It always was a pain joining an old world and having it all be looted for thousands of blocks and working together will friends was difficult once you came across a dungeon or similar structure.
Check out the full write up on Minecrafts webpage and send your feedback over at the official discussion post.