Unreal Engine Issues
Unreal Engine Issues
Multicast RPCs may be sent to clients in a different level with Replication Graph
UE - Networking - Jan 20, 2026UReplicationGraph::ProcessRemoteFunction does not check if the client has the same loaded world as the server when sending a multicast RPCs. For actors that are persisted partway through a seamless ...
Detaching a component may not be replicated to clients
UE - Networking - Jan 13, 2026Because the archetype for scene/static mesh components has a null value for AttachParent, there are some situations where changes to a replicated component's AttachParent are not replicated to clien ...
Detaching a component with "KeepRelative" location rule can result in incorrect location on client
UE - Networking - Jan 13, 2026When receiving a replicated detachment, USceneComponent::PostRepNotifies will call DetachFromComponent with the KeepWorldTransform detachment rule. If the component is detached on the server with th ...
USceneComponent::AttachToComponent may not be called on client depending on replication order
UE - Networking - Jan 13, 2026If the component being attached is received first, OnRep_AttachParent will set bNetUpdateAttachment to true, so USceneComponent::PostRepNotifies will call AttachToComponent. If the attach parent is ...
Replicated timeline may not call Finished event on client
UE - Networking - Dec 9, 2025It seems this can happen if the timeline component on the client receives an update from the server for the final position of the timeline, causing it to be set as no longer playing before it has a ...
net.ReplicateCustomDeltaPropertiesInRepIndexOrder is not respect the cvar for the custom properties
UE - Networking - Nov 5, 2025In our project do not use iris and we use a subclass UExtendAbilitySystemComponent derived from UAbilitySystemComponent. In this subclass, there is a FastArray member variable named ExtendActivatabl ...
Values for InitialOnly replicated arrays can fail to be captured in replay when removed and re-added between checkpoints
UE - Networking - Oct 2, 2025When the first checkpoint is recorded, the correct array properties will be captured in the LifetimeChangelist. When these array items are later removed and another property on the actor is changed, ...
Ensure when calling server RPC from BeginPlay for a component that is not replicated by default
UE - Networking - Sep 18, 2025This seems to occur due to the order in which the component is registered and set to replicate in UActorComponent::OnCreatedFromReplication. The component is first registered with the world, which c ...
Client and server can both get stuck waiting for packet sequence history flush
UE - Networking - Sep 4, 2025The issue occurs when both instances have a significant difference between their last sent and last ack'd sequence number, as they will begin waiting for the sequence history to be flushed for a pac ...
FObjectReferenceCache's ResolveObjectReferenceHandleInternal can return pointers to garbage objects
UE - Networking - Aug 6, 2025A FindObjectFast call may return a pointer to an object marked as garbage. The use of that function in FObjectReferenceCache::ResolveObjectReferenceHandleInternal as well as FNetGUIDCache::GetObject ...