Minecraft 1.21.9 Pre-Release 1

September 18, 2025

The copper age is upon us, heralding the arrival of the first pre-release for this drop. This latest update brings a host of enhancements, particularly focusing on copper golems, alongside adjustments to mannequins and a variety of bug fixes. Unlike the typical Tuesday release schedule, pre-releases are rolled out at different intervals, so enthusiasts should remain vigilant for future updates.

Changes

Minor Tweaks to Blocks, Items and Entities

The copper golem has been refined to only attempt to open chests that are adjacent when it is acting as a passenger.

Minecraft Server Management Protocol

Notifications now utilize the minecraft:notification/ prefix, replacing the previous notification: format.

Technical Changes

The Data Pack version has been updated to 87.1.

Data Pack Version 87.1

Mannequins

The description text for mannequins is now configurable.
Mannequins can accept the minecraft:profile component from spawner items.

Modified Data Fields

profile now mirrors the format of the minecraft:profile component, which has been expanded to allow for overrides. By default, it is set to {}, indicating a static profile where both id and name are absent.

New Data Fields

pose – Defines the mannequin’s stance, with valid entries including:
- standing
- crouching
- swimming
- fall_flying
- sleeping
immovable – An optional boolean indicating whether the mannequin can be moved (default is false).
description – An optional Text Component displayed where a player’s belowscore score would typically appear. If omitted, the default “NPC” label (entity.minecraft.mannequin.label) is shown.
hidedescription – An optional boolean that, when true, prevents any description from being displayed. A mannequin with a hidden description will appear as if a player has no belowscore display.

Commands

The spawnpoint command now optionally accepts a pitch argument.
The setworldspawn command is no longer restricted to the overworld, allowing players to respawn in dimensions like the Nether without a bed or respawn anchor. This command also accepts an optional pitch argument.
Server commands now execute from the respawn dimension by default rather than always from the overworld.
The fetchprofile command now provides clickable text to summon a mannequin with the resolved profile.

Data Components

Modified minecraft:profile

Profiles can now include additional fields that replace various rendering values. If any fields are omitted, the value from the resolved profile is utilized, even if that profile defaults to the standard skin.
New fields include:
- texture – An optional namespaced ID for the skin texture used in rendering, specified relative to the textures folder with a .png suffix. For example, entity/player/wide/steve will render the default wide Steve skin.
- cape – An optional namespaced ID for the cape texture used in rendering, following the same format as the texture field.
- elytra – An optional namespaced ID for the elytra texture used in rendering. If not specified, mannequins using this profile will default to the cape texture, or if that is also absent, the standard Elytra texture when equipped.
- model – An optional model type, which can be either wide or slim.

Entity Data

Modified minecraft:player

Updates to the respawn object include:
- angle has been renamed to yaw and is now a required field.
- pitch has been added as a required field.
- dimension is now a required field.

Loot Functions

minecraft:copy_name

The source field now accepts new context values:
- direct_attacker
- target_entity
- interacting_entity

minecraft:copy_components

The source field now accepts new context values:
- this
- attacker
- direct_attacker
- attacking_player
- target_entity
- interacting_entity
- tool

Fixed bugs in 1.21.9 Pre-Release 1

MC-160528 – End portals fail to negate fall damage.
MC-243759 – Explosions do not damage entities when the distance to their eyes is zero.
MC-300257 – Lightning fails to reset copper golem oxidation.
MC-300294 – Copper golems incorrectly pathfind to chests.
MC-300687 – Copper chains and bars are misorganized in the Creative inventory.
MC-300881 – The skin preview in the skin reporting screen is no longer interactive.
MC-301409 – Acceleration power of fireballs and wind charges is halved when redirected by explosions.
MC-301414 – Scraping oxidation off double chests does not produce particles on the unengaged half of the chest.
MC-301424 – The entity_data item component detection is malfunctioning in resource packs.
MC-301541 – Copper golems no longer sort items while in minecarts.
MC-301569 – Sounds of copper chests and their variants are too quiet and lack quality compared to previous versions.
MC-301573 – Relative teleportation across dimensions is inconsistent.
MC-301798 – Copper golems fail to open chests with specific transparent or non-full blocks positioned above them.
MC-301814 – CustomNameVisible does not function for mannequins regarding the name, not the NPC annotation.
MC-301815 – Mannequin data may be lost when utilizing spawn eggs.
MC-301819 – Mannequins’ name tags are visible when on a team and ridden.
MC-301862 – Clicking a command suggestion in chat occasionally selects half of the new word.
MC-301883 – Entities traversing portals with Motion set above 10 on an axis have their Motion tag reset.
MC-301893 – When a copper golem is leashed by a player and subsequently oxidizes into a statue, it fails to drop the lead.
MC-301951 – The description for operatoruserpermission_level in server management protocol documentation is misleading.
MC-301979 – Copper golems do not accurately check chests.
MC-301984 – Teleporting a player to their own position results in jittery or frozen behavior.
MC-301991 – The deprecated.json file contains some renamed keys pointing to text values instead of the new keys.
MC-302032 – Static profiles no longer resolve texture data unless an id or name is provided.
MC-302089 – The game crashes when flying mobs initiate pathfinding in debug mode.
MC-302092 – A crash occurs when placing iron bars adjacent to stairs, with stairs added to the #bars tag.
MC-302094 – A crash happens when adding blocks to #copper_chests and then placing them next to actual copper chests.
MC-302095 – A crash occurs when adding blocks to #lightning_rods and summoning lightning over them.
MC-302096 – A crash arises when adding blocks to #wooden_shelves, placing them next to a wooden shelf, and then powering the shelf.

Get the Pre-Release

Pre-releases are accessible for Minecraft: Java Edition. To install the pre-release, simply open the Minecraft Launcher and enable snapshots in the “Installations” tab. It is advisable to back up your worlds or run these testing versions in a separate folder, as they may corrupt your main worlds.

For cross-platform server jar and bug reporting, please refer to the appropriate channels.

Feedback is always welcome.

AppWizard