See the linked UDN for more information. It also seems as though calling ForceNetUpdate before making the changes to the fast array results in the changes being properly replicated.

Steps to Reproduce

On a dormant actor with a FFastArraySerializer property, make changes to the fast array and then call ForceNetUpdate.

Expected: the changes made will be replicated to clients

Actual: no changes are replicated

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Won't Fix
ComponentUE - Networking
Target Fix5.0
CreatedJun 11, 2021
ResolvedOct 7, 2021
UpdatedJul 19, 2023