If you kill any mob shortly after loading the world, the white death cloud particles don't appear.
To reproduce
Spawn a mob
Save and quit to title
Rejoin the world
Immediately kill the creeper
→ ❌ The white clouds sometimes don't show up
Attachments
Comments 5
Cause of issue & reproduction:
1. Start a fresh superflat world. (Generate structures has no effect.)
2. With my test Creepers work best, however, the reporter says it affects other types of mobs. When in the superflat world, get yourself a Creeper egg.
3. Spawn the said mob.
4. Let it be spawned in the world and do not kill it. Now, Save and Quit to Title the world.
5. Wait around 2s and rejoin the world.
6. Kill the said mob and you should see that particles fail to play. (The Particles: All/Decreased/Minimal setting has nothing to do with this as it doesn't stop the particles from playing anyway.)
You may need to retry several times to get it working but this should do the trick.
Before marking as Works as Intended, please do note that it requires extensive testing in order to reproduce this bug.
Present in the game since the changes in 1.15 regarding XP orbs dropping immediately as the mob dies instead of dropping when the particles appear.