Quick answer: Unreal Niagara pool returning particles with wrong settings after quality setting change? Pool's pre-warmed systems use old settings - flush pool on quality change.
Player drops graphics quality. Pooled VFX still uses high-quality settings; quality menu setting is ignored.
Flush on quality change
UNiagaraComponentPool::Get()->ReclaimWorldParticleSystems();Empties the pool. Next spawn rebuilds with current settings.
Or pool per quality level
Separate pools for each quality preset. Quality change swaps the pool reference; old pool drains naturally.
Listen for scalability changes
UScalabilityHelpers::OnScalabilityChanged delegate. Flush in the handler.
“Pools optimize for stability. Settings changes break stability assumptions.”
After any scalability event, audit pooled systems. The bug class is invisible until the user changes settings mid-session.