Elytra firework rocket disappears after a few ticks when launched at high speed

The Bug:

A firework rocket used to boost elytra flight can disappear about 4 ticks after launch instead of lasting its full lifetime, which ends the boost. It happens when the player is already flying fast at launch (around boost speed, ~34 blocks/s) and seems to depend on the look angle on the player's look angle.

There are no other entities or blocks near the player. The rocket collides with the player who launched it and explodes through the normal entity-hit path.

Steps to Reproduce:

1. Equip an elytra and hold firework rockets: /give @s firework_rocket[fireworks={flight_duration:1}] 64

2. Set the look angle and gain height: /tp @s ~ 150 ~ 78.94 28.68

3. Start gliding without changing the look angle, and fire one rocket to reach about 34 blocks/s.

4. While still flying at that speed and angle, fire more rockets.

Observed Behavior:

Rockets launched at full speed vanish on the 4th tick. The boost ends immediately.

Expected Behavior:

A rocket attached to a gliding player never collides with that player and lasts its full lifetime (flight duration 1 gives 20–31 ticks).

Evidence

Reproduced in vanilla singleplayer (26.3). To find the cause, I logged events on a Paper test server (26.3) with a diagnostic plugin; plugin only logs, does not change behavior.

Elytra flight at a fixed look angle (yaw 78.94, pitch 28.68), flat world, no other entities nearby, player gliding the whole time.

The first rocket, launched at 14.85 blocks/s, lasted its full lifetime of 24 ticks, and its leftOwner flag stayed false the whole time. The next 12 rockets, launched at 34.65–40.73 blocks/s, already had leftOwner=true on the first tick after launch. They disappeared on exactly the 4th tick instead of lasting their expected 20–31 ticks, and the boost ended each time. The server recorded all 12 removals as the rocket hitting the player who launched it.

The raw log is attached as rockets_flight1.log.

Possibly related

MC-273781: boost from a non-exploding rocket is cancelled when the player collides with an entity. This looks like the same explode() path, with the owner as the entity hit.