Quick answer: Unreal Iris-replicated bitfield bool array losing values after server resize? Iris serializer handles bitfields oddly across array changes - resize via FastArraySerializer with explicit add/remove.

Server inventory grows from 5 to 6 items; client sees flags shifted.

Use FastArraySerializer

Item-level dirty marking. Each item replicates separately; array resize doesn't shift others.

Or use uint8 bitfield

Pack bools into uint8; replicate as bytes. Resize is explicit.

Audit replicated array growth

Each replicated array's growth pattern. Resize is a common bug source.

“Replicated arrays have growth semantics. Bitfield arrays compound.”

For replicated arrays of bool, FastArraySerializer is the right primitive. Migration cost: one-time; bug class: gone.

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