LevelEditor: "Replace Actor" marks level as dirty even when using external actors

UE - World Creation - Worldbuilding Tools - Jul 15, 2024

When using external actors, adding/removing/replacing/editing an actor instance inside a level does not cause any modification to the Level package, which helps reduce contention for the map file on ...

[CrashReport] Crash related to asset export - UnFbx::FFbxExporter::FillExportOptions() [fbxmainexport.cpp:152]

Tools - Sep 28, 2017

This is a trending crash coming out of the 4.18 previews. It seems to be related to exporting assets from the editor. User DescriptionsWhen Exporting assets (static meshes) multiple times via RIGHT ...

Crash when Reimporting SpeedTree asset with Billboard Material reset to the default World Grid Material

UE - Editor - Content Pipeline - Import and Export - Feb 7, 2017

A crash occurs when reimporting a SpeedTree asset after clearing the material billboard element and setting it to the default world grid material. The licensee reporting the issue mentions to worka ...

Splitting Transform in Collapsed Graph Crashes UE4

UE - Gameplay - Blueprint - Feb 10, 2017

Splitting Transform in Collapsed Graph Crashes UE4. When this is done the editor crashes and that actor can no longer be opened without causing a crash. ...

Orientation Warping breaks incoming poses where bones are in component space

UE - Anim - Gameplay - Apr 17, 2025

The orientation warping node breaks incoming poses where bones are already in component space. This is because, in EvaluateSkeletalControl_AnyThread, we are repeatedly setting bone transforms direc ...

User-defined InstancedStaticMeshComponent subclass misbehave in SCS Editor

UE - Framework - Blueprint Editor - Oct 13, 2025

Context Users can create InstancedStaticMeshComponent (ISMC) (blueprint) subclasses. Any ISMC class can be added to an actor blueprint. When a mesh is selected and transforms are added to the Insta ...

Changing the navigation for the root of a widget blueprint will cause a crash

UE - Editor - UI Systems - Sep 28, 2015

Changing the navigation of the root of the widget blueprint will cause the editor to crash ...

Crash When Opening a DataTable Based Off a Struct With a Timecode Variable

UE - Anim - Sequencer - Mar 30, 2020

When a datatable is based off a struct with a timecode variable it will crash when opening. Found in 4.24.3 CL#11590370 Reproduced in 4.23.1 CL#9631420, 4.25 Preview 4 CL#12366721, 4.26 CL#12123513 ...

Custom iOS icons don't appear on device for Windows BP projects (Binary Build)

UE - Platform - Mobile - May 4, 2018

iOS icons have stopped working for Windows BP projects again; this does not occur on Mac. It also does not occur when using a source build from p4 (only on a binary build from the launcher). Note t ...