Java Edition 24w21a

24w21a is the fifth snapshot for Java Edition 1.21, released on May 22, 2024,^[1] which introduces custom jukebox music and fixes bugs.

Target selectors

• Added @n entity selector, selecting the nearest entity.
  • This functions as @e[sort=nearest,limit=1].
  • Additional requirements may still be provided; for example: @n[type=pig] selects the closest pig.

Game rules

• Added new entitiesWithPassengersCanUsePortals gamerule.
  • Defaults to false.
  • When true, entities with passengers can use nether portals, end portals and end gateways, and the waiting time for being transported through the portal is completely skipped.

Tags

• Added the following block tag:
  • air: air, cave_air, and void_air
    • Contains all blocks that resemble air.
• Added the following damage type tags:
  • panic_causes: contains #panic_environmental_causes, arrow, dragon_breath, explosion, fireball, fireworks, indirect_magic, magic, mob_attack, mob_projectile, player_attack, player_explosion, sonic_boom, sting, thrown, trident, unattributed_fireball, wind_charge, wither, and wither_skull
    • Contains damage types that cause panic in passive animals, i.e. mobs that run away when attacked.
  • panic_environmental_causes: contains cactus, freeze, hot_floor, in_fire, lava, lightning_bolt, and on_fire
    • Contains damage types that cause panic in aggressive animals that can panic, i.e. mobs that retaliate when attacked (wolves, polar bears (adults) and pandas).

Doors

• Doors of different materials now default to being placed oriented together to form a double door instead of both being placed with the hinge on the same side of the block.

Piston

• Reverted to the old sounds.
• Lowered volume of original sounds to address the initial feedback of pistons being too loud.

Vault

• Added a new sound on vault to help players understand they've already looted a vault.

Bolt armor trim

• Can now be duplicated using a waxed block of copper.

General

• Animals now panic for 2 seconds after taking damage (down from 4).
• Animals now panic based on the damage caused by predefined damage source types.

Pandas, wolves and adult polar bears

• Now only panic from cactus, freezing, fire and lightning bolt damage.

Trial chambers

• Are less likely to generate in the deep dark.

/attribute

• The uuid and name arguments have been replaced with a singular id argument.

Attributes

• Attribute modifiers no longer have a UUID and name combination.
• Instead, attribute modifiers are now uniquely identified by a namespaced ID, similar to other resources.
• The ID of a modifier uniquely identifies it in the set of modifiers for a single attribute.
  • Using the same ID for different modifiers is allowed as long as the modifiers are for different attributes.
• Existing built-in modifiers are upgraded to new IDs.
• Existing custom modifiers are upgraded to the GUID as an ID in the minecraft namespace.

Item stack attribute modifiers

• The uuid and name fields have been removed.
• Attribute modifiers now have an id (namespaced ID) field.
  • This is a unique identifier per attribute for the modifier.

Entity attributes

• Are now stored in attribute format:
  • id, renamed from Name.
  • base, renamed from Base.
  • modifiers, renamed from Modifiers.
    • Now stores modifiers in the same format as modifiers in attribute_modifiers item stack components:
      • id, replaces UUID and Name.
      • amount, renamed from Amount.
      • operation, renamed from Operation, now a named constant instead of an int:
        • add_value - previously 0.
        • add_multiplied_base - previously 1.
        • add_multiplied_total - previously 2.

Enchantments

• Attribute effects
  • Fields:
    • name & uuid have been removed, replaced by id.
    • id: the namespaced ID of the attribute modifier to add.
      • This will be postfixed with the slot name when the enchanted item is equipped in a slot.
      • Must be unique to avoid different enchantments (or other systems) interfering with each others.

Entity effect types

• damage_item.
• The damage is not applied to items held by players in creative mode.
  • Hit block parameters.
    • Entities: this.
    • Enchantment level.
    • Origin.
    • Block state.

Effect components

• minecraft:hit_block:
  • Condition context: changed to take a hit block parameter - this is the entity hitting the block.

Tags

• Some registry types that used legacy data pack directory names (based on plural name of element) have been renamed to match registry name.
  • Affected directories:
    • structures -> structure
    • advancements -> advancement
    • recipes -> recipe
    • loot_tables -> loot_table
    • predicates -> predicate
    • item_modifiers ->item_modifier
    • functions -> function
    • tags/functions -> tags/function
• Removed breeze_immune_to damage type tag.
• Removed music_discs item tag.

Predicates

• New item sub-predicate available as jukebox_playable.
  • Matcher for jukebox_playable component (like music discs).
  • Fields:
    • song - optional id, list of ids or tag for jukebox song to be matched.
• Player predicate
  • The gamemode field has been changed to accept a list of gamemodes.

Data pack

• The pack format version is now 45.

Item components

• Added the jukebox_playable item component.
  • If set, the item can be inserted into jukeboxes to play a song.
  • Format: object with fields.
    • song: jukebox song id.
      • The song that is played by the jukebox when this item stack is inserted.
    • show_in_tooltip: boolean (default: true).
      • If false, the name of the song isn't shown in the tooltip.
      • This was formerly controlled by the hide_additional_tooltip component on music discs.
    • e.g. jukebox_playable={song:'minecraft:precipice'} jukebox_playable={song:'minecraft:precipice', show_in_tooltip:false}.

Jukebox

• Added a jukebox song registry which is loaded from data packs.
• Path to jukebox song definition is data/<namespace>/jukebox_song/<id>.json.
• Fields in definition:
  • sound_event - sound event that is streamed when played by a jukebox.
  • description - the name of the song that is displayed in the hover tooltip represented as a text component.
  • length_in_seconds - length of the song in seconds as a positive float.
  • comparator_output - the redstone signal output by a comparator when played in a jukebox, between 0 and 15.

Performance

• Improvements to the disconnection screen.
• In some cases client now stores detailed information about disconnection (similar to crash reports).
• When that happens, new "Open Disconnection Report Directory" button is added to the disconnection screen.
• When server provides link for bug reporting, it's also added as a button to the disconnection screen.

Realms

• Any member of a realm can now upgrade a world.
• In the realms main screen, all online players of a realm are displayed.
  • When hovered, a tooltip is shown with each player's head and name.

Resource pack

• The pack format version is now 34.
• Added the block.vault.reject_rewarded_player sound event.

Server

• Pause menu now can include a list of links provided by server.
• Server can now provide list of links to client.
• Servers can add custom details to crash and disconnection reports.
• New clientbound packet custom_report_details is available in configuration and game protocols.
• This packet contains a list of key-value text entries.
• If received, contents of this packet are added in a separate section to any crash or disconnection report generated during connection to this server.

Server link

• Servers can now provide a list of links to clients.
• If client has received any links, a new button called "Server Links..." shows up in pause game screen.
  • To make space for that button, "Report Bugs" and "Give Feedback" buttons might be moved into a sub-screen if necessary.
• New clientbound packet server_links is available in configuration and game protocols.
• On receival, client makes links available from pause menu.
• Link labels can be built-in or custom (i.e. any text).
• Some built-ins also have special functionality:
  • report_bug:
    • Link is displayed on disconnection screen, if disconnection was caused by packet handling error.
    • Link is included as a comment in disconnection report.
• Added bug-report-link to server.properties to allow vanilla server to configure report_bug links.
  • If this field is non-empty, server sends that link to clients.
  • This field should contain well-formed URL.

Shaders

• The blend block in core shader definitions has been removed, as it was not used.
• The position_color_tex shader has been removed, replaced with the pre-existing position_tex_color.
• The glint_direct shader has been removed, replaced with the pre-existing glint shader.
• The armor_glint shader has been removed, as it was unused.

Armor

• Burn time reduction effect now stacks on multiple armor pieces.
• Blast knockback reduction effect now stacks on multiple armor pieces.

42 issues fixed

From released versions before 1.21

• MC-67 – Entities with passengers cannot travel through portals.
• MC-31819 – Hunger saturation depletes on Peaceful.
• MC-78473 – Mobs don't panic when hit with a summoned or dispensed potion of harming.
• MC-116279 – Non-player entities going through nether portal do not generate portal in the Nether if none exists.
• MC-151648 – Non-player entities cannot travel through unlinked nether portals.
• MC-170103 – Untamed wolves only beg for food while being angry and jumping.
• MC-253209 – Some mobs will no longer panic when receiving poison/wither damage.
• MC-260346 – Custom music discs cut off when vanilla disc would normally end.
• MC-262469 – The "Remote Getaway" advancement isn't granted upon traveling through end gateways while riding boats.
• MC-266290 – Double doors do not automatically form between waxed and unwaxed copper doors, even of the same variant.
• MC-266586 – Trial chambers can spawn directly inside the Deep Dark biome.
• MC-266626 – Breeze doesn't stop attacking the player when it enters on the same team.
• MC-267498 – Operation names in /attribute and item modifiers' set_attributes are different.
• MC-267967 – Breezes ignore the deflects_projectiles entity type tag.
• MC-268438 – Baby armadillos can still eat while rolled up.
• MC-269034 – Wolves no longer teleport while trying to pathfind out of lava.
• MC-269351 – The Bolt armor trim cannot be duplicated with waxed copper block.
• MC-269370 – Sharp lag spike caused by incorrect upper limit on particles created by mace smash attack.
• MC-269460 – Thorns enchantment doesn't work when entities are hit by wind charges.
• MC-269964 – Ominous item spawners are missing an NBT load for spawn_item_after_ticks.
• MC-269988 – New potion effects don't apply their respective behaviors when creeper explodes.
• MC-270024 – When drinking ominous bottles, Bad Omen of higher levels can be overriden by lower amplifiers.
• MC-270377 – Wind charges can be hit and redirected the moment they are thrown.
• MC-270573 – Mounted entities are immune to wind charge damage.
• MC-270749 – Remote Getaway advancement is not granted when entering a gateway by throwing an ender pearl next to it.
• MC-270808 – Any item in the armor.body slot protects wolves from taking damage.

From the 1.21 development versions

• MC-271458 – Channeling tridents no longer summon lightning bolt when hitting a lightning rod during a thunderstorm.
• MC-271573 – Attribute enchantments don't behave properly on armor.
• MC-271634 – Custom enchantments don't appear in the Creative menu.
• MC-271718 – Crash when randomized_int_state_provider is applied to blocks lacking the property.
• MC-271753 – Crash due to overflow inside cost calculation in by_cost_with_difficulty.
• MC-271856 – Crossbows enchanted with Quick Charge do not benefit from its effects when used in the offhand.
• MC-271868 – Frost Walker replaces flowing water now.
• MC-271901 – Entity effect "play_sound" field "pitch" value upper limit is 1.0 instead of 2.0.
• MC-271911 – Frost Walker no longer works with void or cave air.
• MC-271914 – Soul Speed enchantment doesn't emit particles when the entity is controlled by a player.
• MC-272039 – Soul Speed uses durability in Creative mode.
• MC-272182 – Knowledge books no longer function properly with a stack size of 1 in Survival/Adventure mode.

From the previous development version

• MC-272042 – If players have max health over 20 and die, when they respawn they will have 20 health instead of their max health.
• MC-272043 – The game crashes when entities die while having the Oozing effect.
• MC-272075 – Attempting to step up while controlling entity and moving fast often glitches.
• MC-272084 – Creepers with potion effects no longer create area effect clouds upon exploding.