Ray tracing scene doesn't reflect WPO with instance custom data

UE - Graphics Features - Ray Tracing - Sep 19, 2025

When custom instance data is used to calculate WPO in a Material and applied to an ISM the WPO value in the Lumen scene (ray tracing scene) is different than the visible scene resulting in incorrect ...

Mutable custom versioning issue from 5.5->5.6

UE - Anim - Mutable - Sep 19, 2025

In 5.6, a handful of new entries in `FCustomizableObjectCustomVersion` were added, including `SetDisplayNamePropertyAsPinNameOfTableNodes`. Looking back at the history, `SetDisplayNamePropertyAsPinN ...

3D Grass may not appear in Path Tracer renders

TM - Rendering - Sep 19, 2025

Reported in SF [Link Removed] Path Tracer renders of images with 3D grass may not display 3D grass in the foreground of an image. The 3D grass material will not appear or may appear to cut off at s ...

Mutable references MetaHumans heads directly, but DNA Assets are private

UE - Anim - Mutable - Sep 18, 2025

When we switched our project to 5.6.1 This error appeared on build. The compilation of the Mutable assets in the editor is not reporting any issue. ...

Ensure when calling server RPC from BeginPlay for a component that is not replicated by default

UE - Networking - Sep 18, 2025

This 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 ...

Seam visible when using a material with BumpOffset on a Nanite mesh

UE - Graphics Features - Nanite - Sep 18, 2025

When a material that uses BumpOffset is fed into the Emissive Color of Surface Opaque Default Lit material and then applied to a nanite mesh, a visible seam can be seen along edges and the intersect ...

Setting a struct bool property (bitfield) to itself writes the wrong value

UE - Framework - Blueprint Compiler - Sep 17, 2025

There's an issue when assigning a bitfield bool to a native bool in Blueprints. Currently, the engine erroneously treats the memory for a local bool as a uint8 bitfield, which is undefined behavior. ...

Nanite Skeletal Meshes Invalidate VSM

UE - Graphics Features - Nanite - Sep 17, 2025

Nanite Skeletal Meshes will always invalidate VSMs, even with their Shadow Cache Invalidation Behavior set to Rigid. This does not match the behavior of non-Nanite Skeletal Meshes. ...

Controller::OnPossessedPawnChanged broadcasts (Pawn->null) but not (null->Pawn) during AGameModeBase::RestartPlayer()

UE - Gameplay - Sep 17, 2025

Context AController has a blueprint assignable delegate that fires when the possessed pawn changes. This should fire in both singleplayer and networked games. The bug is reproducible in single play ...

Hovering items at bottom right of Content Browser does not display tooltip and causes cursor flicker

UE - Editor - Applied Usability - Sep 17, 2025

When hovering over items located at the bottom right corner of the Content Browser while the Editor is maximized, the tooltip is not displayed. It seems that the tooltip would extend beyond the edge ...