MC-248076Specific type of Firework Rockets won't stack with each other after use
This only happens when firework rockets are generated via command with no NBT data other than a custom display or name (meaning no decoration). When the stack is split in some way and one of the smaller stacks is used, that second stack loses the ability to stack with the unused set. This includes use when launched, used with an elytra, and shot out of a dispenser. When an additional stack is used, it can combine with the other used stack again.
Further inspection with advanced tooltips shows that the number of NBT tags changes from 1 to 2, and an even closer look reveals that "Fireworks": {} is added to the NBT after a stack is used.
The attached video shows this in detail (poor quality to fit under the 10MB limit).
![[Mod] Jiingy](../../../data/avatars/users/91802.png){kind=small}
Created Issue:
Specific type of Firework Rockets won't stack with each other after use
This only happens when firework rockets are generated via command with no NBT data other than a custom display or name (meaning no decoration). When the stack is split in some way and one of the smaller stacks is used, that second stack loses the ability to stack with the unused set. This includes use when launched, used with an elytra, and shot out of a dispenser. When an additional stack is used, it can combine with the other used stack again.
Further inspection with advanced tooltips shows that the number of NBT tags changes from 1 to 2, and an even closer look reveals that "Fireworks": {} is added to the NBT after a stack is used.
The attached video shows this in detail (poor quality to fit under the 10MB limit).
Environment
Windows 10 Home 20H2 19042.1415, x64
Java 17.0.1
![[Bot] Arisa](../../../data/avatars/users/43007.png){kind=small}
![[Mod] turbo](../../../data/avatars/users/92867.png){kind=small}
Windows 10 Home 20H2 19042.1415, x64
Java 17.0.1
![[Mojang] Timur Nazarov](../../../data/avatars/users/18945.svg){kind=small}
Normal
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This issue could possibly be related to
MC-5413andMC-17336Confirmed in 1.20.3 pre 2
Also here is the updated command that works
/give @p minecraft:firework_rocket{display:{Name:'
{"text":"Bug Report","color":"red"}'}} 16
When the player uses the firework rocket item, the game adds an empty "Firework {}" tag to the item stack, leading to the inability to stack.
Here, the first item is one which was not used, and the second was.
The source seems to be 'appendTooltip()' inside FireworkRocketItem (MCP 1.20.2) where the game tries to append the "Firework {Flight: [x]}" tag, but since the rocket does not have a flight duration the tag is just left empty.
This has been fixed in 24w09a. I attached two videos: one demonstrating a fixed version, the other demonstrating a bugged version.