The bug
Fireworks not rotated into the direction they're flying in. Instead, their rotation depends on the player's rotation and viewing angle.
When a firework rocket flies sideways (for example when shot by a dispenser), it is not rotated correctly.
Example
[media]Linked issues
is duplicated by 5
MC-160460
Firework fired from dispenser oriented up or down are wrongly positioned
Resolved
MC-167563
Firework texture bug
Resolved
MC-190833
Bug with firework texture
Resolved
MC-227306
Fireworks do not point the right direction when fired from dispensers
Resolved
MC-241155
indirect fireworks
Resolved
relates to 2
Attachments
Comments 31
Affects 20w20a
This happens because particles in java are rotated according to the player's looking direction, and apparently firework rockets are affected by the same thing.
21 more comments
@unknown I made you the reporter of this ticket, so you can update the affected versions yourself now 🙂
Also relates to MC-166063