Variant Manager: LevelVariantSets asset corruption after rename or duplicate

UE - Editor - Content Pipeline - Oct 24, 2025

When renaming or duplicating a LevelVariantSets asset that contains a Director Blueprint, the internal DirectorClass reference becomes mismatched. Although the DirectorBlueprint pointer updates corr ...

Classes in TargetDenyList modules are still referenced from Components on BlueprintGeneratedClasses and cause runtime warnings

UE - Foundation - Feb 25, 2024

Other than the presence of the error and the performance cost of looking for a package on disk that does not exist, there are no behavioral problems. When running with legacy (non-iostore) pakfiles ...

[CrashReport] UE4Editor-ApplicationCore.dylib!FMacWindow::ApplySizeAndModeChanges()

UE - Platform - Apple - Oct 27, 2017

This is an early trending Mac crash in 4.18. Users have not provided any descriptions of their actions when the crash occurred. Callstack from LogLogAssetRegistry: Asset discovery search completed ...

[CrashReport] UE4Editor-ApplicationCore.dylib!invocation function for block in FMacApplication::DeferEvent()

UE - Platform - Apple - Dec 1, 2017

This is an infrequent Mac crash in 4.18.1. Users have not provided any descriptions. Callstack from Log2017.11.27-02.08.07:839][947]LogMaterial: Missing cached shader map for material FLightmassMat ...

Removing components from Landscape with simplified collision results in assertion

UE - LD & Modeling - Terrain - Landscape - May 18, 2017

Performing operations on a Landscape with simplified collision can result in an assertion ...

Using blueprint debug step into BlueprintInterface function, occur crash.

UE - Gameplay - Blueprint Editor - Nov 10, 2017

If StepIn is performed on a module for which the Interface function is not defined, a crash will occur. ...

Crash on bake pose when skeleton contains a virtual bone

OLD - Anim - Jan 22, 2018

When a skeleton contains a virtual bone, performing Bake Pose can crash the editor. ...

Crash removing a pin from an in-use struct, and then undo/redo

UE - Gameplay - Blueprint - Jun 7, 2017

REGRESSION No Crash occurs when the user deletes a pin from a struct that is in use, then performs undo and redo on the deleting. ...

Framerate drops when using SceneCaptureComponents with a RenderTarget in VR

UE - Platform - XR - May 14, 2018

Using SceneCapture in packaged VR projects causes poor performance. Also observed with SceneCaptureCube Does not occur in 4.18 ...

Crash when Undo after deleting a Material Layer of a Material Instance.

UE - Rendering Architecture - Materials - Apr 2, 2025

In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...