The bug
The particles for effects from beacons are reduced/faded. These particles become fully visible if other effects (with hideParticles=true) are added.
How to reproduce
Create a beacon and enable an effect
Give yourself a hidden effect
/effect give @s night_vision 100 0 true
→ ❌ Notice that fully visible particles are visible
Related issues
Attachments
Comments

Here are the combinations I observed, all seem correct except this case.
Hidden | Ambient | Normal | Result |
---|---|---|---|
|
|
| Hidden ✔ |
|
| ✔ | Normal ✔ |
| ✔ |
| Ambient ✔ |
| ✔ | ✔ | Normal ✔ |
✔ |
|
| Hidden ✔ |
✔ |
| ✔ | Normal ✔ |
✔ | ✔ |
| Normal ❌ |
✔ | ✔ | ✔ | Normal ✔ |
Can confirm in 20w51a.
Can confirm in 21w03a.
Can confirm in 21w06a.
Can confirm in 1.16.5 and 21w08b.

This is a duplicate of MC-96535.
Thank you for your report!
We're tracking this issue in MC-96535, so this ticket is being resolved and linked as a duplicate.
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