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 ...
[Enhanced Input] The action instance data is incorrectly reset when you call "Add mapping context" on the same mapping multiple times
This is somewhat related to [Link Removed] and was brought up by a [Link Removed] Setting the CVar input.bRespectIMCPriortyForTriggers to false resolves the issue, but would re-introduce [Link Remo ...
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 ...
bWeldSimulatedBodies not replicated with attachment
UE - Simulation - Core - Jan 13, 2026The bWeldSimulatedBodies attachment parameter is not replicated to clients, both in USceneComponent's attachment replication handling and in AActor's FRepAttachment struct. If AttachToComponent is c ...
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 ...
Not possible to force the Skeleton attribute to None on a default asset pipeline preset
UE - Editor - Content Pipeline - Import and Export - Jan 9, 2026I guess that when the default value of the pipeline is None, the editor will silently pick the skeleton that is in the same folder of where you are importing. If the UI is active you can then force ...
Iris - Ensure hit when destroying a torn off actor from AActor::TornOff
UE - Networking - Iris - Dec 11, 2025As of CL 42014318, StopReplication requests that occur during ReceiveUpdate are delayed until all received data from the update is finished processing, including if the actor is torn off. However, i ...
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 ...
Texture Streaming can randomly streams in all Mips, causing large memory spikes
UE - Rendering Architecture - RHI - Dec 5, 2025A possible race condition allows texture instance views to read uninitialized bounds, causing either garbage or zero screen size values to be returned by FRenderAssetInstanceAsyncView::GetRenderAsse ...