Double slab IDs not in parity with java, despite the splitting of IDs

Attribute modifier on an item with the first and/or last 2 integers of the UUID being 0 are non-functional

Operation names in /attribute and item modifiers' set_attributes are different

Teleporting in the air is considered flying by server

Trident has a number of unused NBT due to inheriting all arrow NBT

The eye lines of bats hanging from blocks don't face in directions in conjunction with their models

Large models that cross multiple blocks do not light up model partially based on each block's light level

Typing out the last quote of a block state key, and then pressing tab prepends another quote at the front of the key

/scoreboard players add/remove doesn't allow negative values

Unused texture: misc/white.png

Several realms textures use outdated textures (and show old generation)

Item display with display set to head does not face the same direction as equipped on an entity

#nether_carver_replaceables contains several blocks that can't generate in the nether

Enchantment glint mcmeta file not used anymore since texture rename

Advancements gui doesn't allow more than 26 tabs

Predicates don't allow dimension nor biome tag in location check

Server MOTD doesn't support raw JSON text, and requires § for formatting

Texture references for mob effects and paintings are missing prefix

Block entity ID of spawners doesn't match block/item ID

Advancement icon is required, but can be set to air (showing no/an empty icon)

Advancement description is required, despite having specific behaviors if it contains no text

Announced advancement's brackets in chat have no hover event

Advancement titles of 0-characters long are valid, but title isn't optional

Advancement description text cuts words in weird places if title is too short

Effect duration on players decreased by 1 before a command can see it, but not on mobs

Sound volume is clamped between 0 and 1 too late

Teleporting a shulker riding an entity makes standing on it jiter

A tag missing an entry will output it as missing once for each loaded data pack

Carrot/Warped Fungus on a stick doesn't increase use stat when held in offhand