Damage debuff icons don't always show on enemies in 24-man content

[Kryogenik]

ISP: BT Business Infinity Premium
Type of Internet Connection: Fibre Optic
Internet Connection Speed: 73Mbps
Date & Time: Always
Frequency: Always
World: Leviathan
Character Name: Cherry Muffin
Retainer Name: None
NPC Name: None
Monster Name: All 24-man bosses
Class/Level: BRD60
Party or Solo: Party (Full alliance of 24)
Race: Lalafell F
In-Game Time: Always
Area and Coordinates: All 24-man content (Crystal tower, Weeping City etc.)
Housing: None
Steps:
1. Fight bosses with a full alliance
2. Notice sometimes debuff icons don't appear on boss (eg Venomous Bite or Windbite) if too many debuffs are on the bar
3. Reapply debuff, watch as the pop-up indicator says your attack has landed (eg when it says "+ Venomous Bite"
4. Notice debuff icon STILL doesn't appear on boss
5. Switch UI options to "Display only detrimental effects you inflict."
6. Notice boss debuffs from other players don't show anymore
7. Reapply debuffs of your own again
8. Notice sometimes debuff icons STILL don't show on boss

Basically, if too many detrimental effects are applied to a boss, some of them don't show on the bar. This is understandable if there is a limit to what can be displayed, such as in 24-man content when a large number of players are inflicting detrimental effects to the same enemy.
However... If you turn OFF other player effects the limit is STILL applied to the bar in the background, so effects you inflict are still not shown on occasion. This defeats the purpose of turning off other player effects so you can only see your own.

[Mholito]

It is because only the first 30 effect slots are set to be visible regardless of your settings. It's technically not a bug, just a weird quirk with how the servers work at the moment. I hope they change it at some point.