Loading error for editor only BlueprintNativeEvent functions

UE - Framework - Blueprint Compiler - Sep 26, 2025

The editor-only function in the native parent class is not compiled in the game module, which is why we're getting this error. The Blueprint compiler should follow suit during cooking and not genera ...

FBlackboardKeySelector filters aren't applied when recompiling blueprint if a behavior tree asset containing the blueprint added as a service is closed, or if the blueprint is reparented.

UE - AI - BehaviorTree - Sep 24, 2025

Context In Behavior Trees, BT Services can be added to nodes. Those services can have configurable FBlackboardKeySelectors. BlackboardKeys are variables on a blackboard that the behavior tree can r ...

Post Process Animation Blueprint Crash When Using Blend Node

UE - Anim - Runtime - Anim Blueprints - Sep 24, 2025

When using a Blend node inside a Post Process Animation Blueprint, the editor crashes while rendering thumbnails. The crash occurs because USkeletonThumbnailRenderer attempts to draw a thumbnail wit ...

New folder shortcut (Ctrl+Shift+N) does not work in multi-Content Browser layouts until a folder is manually focused

UE - Editor - Workflow Systems - Sep 23, 2025

In multi–Content Browser layouts, the New Folder shortcut (by default Ctrl+Shift+N) does not work immediately after switching to another Content Browser tab. It appears that the editor does not auto ...

Applying downscale causes textures to display unexpectedly on widgets

UE - Editor - UI Systems - Slate - Sep 22, 2025

When applying downScale 2.0 to UI textures to reduce resolution, unintended display issues occur on widgets, such as: ・The border of box-shaped Widgets with DrawAs set to “Box” becomes thinner ・Dot ...

In 5.6, bWarningsAsErrors does not work with clang

UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2025

In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes:    [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...

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

UE - Rendering - 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 ...

Nanite Skeletal Meshes Invalidate VSM

UE - Rendering - 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 ...