Swapping the Child Actor Class of a ChildActorComponent back to a previously selected BP leads to an Editor crash from illegal Renaming

UE - Framework - Components - Sep 11, 2024

A fatal error occurs if we change a Child Actor Class from one BP (ex. "BP_A") to a different BP ( ex. "BP_B") and later change it back to the first BP (ex. "BP_A") without compiling the BP between ...

Variant manager crash in UPropertyValue::HasValidResolve

UE - Editor - Content Pipeline - Variants - Nov 21, 2024

in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...

Modifying the properties of a ChildActorComponent in a child blueprint can modify the parent actor ChildActorComponent properties.

UE - Framework - Blueprint - Dec 10, 2024

When a property of a ChildActorComponent is modified in a child class, the parent ChildActorComponent class can also get modified. This happens when the Parent blueprint actor has a ChildActorCompo ...

nDisplay is not linking correctly the Camera Components inside the nDisplayConfig.uasset with display viewports when their Projection Policy is set to Camera. This issue appears when a packaged game is launched from the Switchboard as "Packaged Game".

UE - Virtual Production - nDisplay - Jan 27, 2025

When launching a packaged game from the nDisplay Switchboard, the nDisplayConfig file fails to link the cameras to the viewports. Inside the log generated by the Switchboard an error is displayed th ...

Closing a Geometry's Collection Dataflow Editor window when the ChaosVehiclePlugin is enabled is crashing the Unreal Editor when running it with the -stompmalloc flag

UE - Runtime - Simulation - Jan 27, 2025

As the title describes, closing a Geometry's Collection Dataflow Editor window when the ChaosVehiclePlugin is enabled is crashing the Unreal Editor when it is running with the -stompmalloc flag. The ...

Regression: FAnimInstanceProxy memory leak when BeginDestroy() called on UAnimInstance before USkeletalMeshComponent

UE - Runtime - Animation - Feb 10, 2025

In UE 5.5, the fix applied by CL 36529858 in ue5-main updated USkeletalMeshComponent::ClearAnimScriptInstance() to call AnimScriptInstance::UninitializeAnimation() on the animation instance. This, i ...

Backwards-compatibility broken for the CDOs of Python-generated Unreal Types because of missing redirectors

UE - Editor - Feb 11, 2025

Previously, all Unreal Types generated by python scripts would be created inside package "/Engine/PythonTypes". This was changed by [CL 32478991 in ue5-main branch], which meant to "remove the restr ...

OnComponentWake Event does not trigger when the physical body is awoken by a Force

UE - Runtime - Simulation - Feb 27, 2025

OnComponentWake Event does not trigger when the physical body is awoken by a Force. The steps described on Steps To Reproduce is enough to replicate this behavior. The OnComponentWake event is only ...

Chaos Modular Vehicles Examples desynchronizes easily

UE - Runtime - Character - Feb 27, 2025

Chaos Modular Vehicles Examples does not replicate properly and it's easy to reach a state of desynchronization where the state stops being replicated and position/rotation of cars mismatch. As an ...

InstancedStruct Local Variables do not work

UE - Core - Systems - May 7, 2025

The licensee has noticed that local variables of type InstancedStruct return nullptr. The setup is a verification of the behavior. Class variables work normally. I've tested this behavior on every v ...