Mobs can suffocate below blocks, if the eye height isn't inside the collision box

Spawn chunks changed size from 16/17 to 23 side length

Entities stay on the global list even when the chunk unloaded

Changing the render distance can cause chunks to stay loaded

/forceload loads an area one chunk larger than specified

/forceload query can not be run from functions or command blocks

Scheduled ticks get lost when leaving chunks (Redstone components get stuck)

Being close to the end island causes out of memory and file descriptor exhaustion

Errors, warnings and 10 second freeze on loading list of singleplayer worlds

Signing-GUI of Book and Quill does not interpret TextComponent of the Author

Minecarts drop their items offset in the positive direction

Breaking inventories next to walls can cause items to glitch away

Crash while using a lot of pistons/slime blocks (java.lang.IllegalArgumentException: Cannot get property)

Moving blocks can move entities into other moving blocks (also when they move in a different direction)

Moving blocks use 0,0,0 as surrounding to calculate their bounding box

Entities can fall through moving fences

Removing a powered observer does not cause all needed updates

Entities inside the base of an extended piston get moved in front of it on retraction

Fences and cobble walls moved by pistons don't move entities in the upper part of their collision box

Chunk-wise entity lists often don't get updated correctly (Entities disappear)

Crash when 32 or more pistons retract in a single chunk (IllegalArgumentException)

Hoppers cannot pull items from double chests if second chest is blocked

Old strongholds "change position" and distance to origin is too high

Slime blocks moved by pistons often fail to bounce up the player

Pistons warp entities too much (Pistons pull entities in/through blocks)

Items don't move up when stuck in block

Pistons don't move/bounce entities

Retracting blocks don't move/bounce entities correctly

Slime blocks moved by pistons don't move entities (but only set the motion)

Slimes/magma cube with NoAI-Tag still can damage the player

When unloading a hopper minecart it gets unlocked

Snow blocks receive (useless) random updates and can get destroyed when there is a light glitch

When using spawn eggs on fences the mobs fall through

Nights don't get skipped when the last player is set to specator mode

Crash: IndexOutOfBoundsException on Tesselating block in world

Block collision box issues (mobs glitch through blocks and more)

Mobs glitch through the ground under certain conditions

When using /stop server executes the shutdown sequence twice (and hangs if players are online)

Redstone torches (and other redstone components) have inconsistent timings

Bad hit boxes and eye positions

Pigs (without swords) spawn pigmen with swords when struck by lightning

Players appear offset for other clients after going through nether portals

Structures (witch huts, nether fortresses etc.) don't get saved with the world file

Passwords containing certain characters won't work properly on a linux system

Entities other than the player can't leave the end

Donkey/Mule item duplication

Dispensers spawn mobs without offset along the y-axis