Put the summary of the bug you're here
What I expected to happen was...:
I expected the firework to function by bursting in a rainbow made of many colors.
What actually happened was...:
The firework crashed due to a particle bug, after it worked correctly, and displays the error "n must be positive."
Also, the launcher says my game is modded, when it has no functioning mods in my game files.
Steps to Reproduce:
1.First, use /summon in a command block to spawn the firework. It will work for a bit, than crash on a particle.
2. /give gives you a firework that when used, crashes.
3. The firework used to make the entity works just fine with no crashes.